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                                                                EXHIBIT 10.17





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                 AGREEMENT AND PLAN OF MERGER AND REORGANIZATION


                                     among:


                               DNA SCIENCES, INC.,
                             a Delaware corporation;


                             PIPO ACQUISITION CORP.,
                             a Delaware corporation;


                                       AND


                                   PPGX, INC.,
                             a Delaware corporation;


                           ---------------------------

                          Dated as of December 17, 2000

                           ---------------------------




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SECTION 1. DESCRIPTION OF TRANSACTION.............................................................................1

         1.1      Merger of Merger Sub into the Company...........................................................1

         1.2      Effect of the Merger............................................................................1

         1.3      Closing; Effective Time.........................................................................1

         1.4      Certificate of Incorporation and Bylaws; Directors and Officers.................................2

         1.5      Conversion of Shares............................................................................2

         1.6      Stock Options...................................................................................6

         1.7      Closing of the Company's Transfer Books.........................................................7

         1.8      Exchange of Certificates; Escrow Shares.........................................................7

         1.9      Appraisal Rights...............................................................................10

         1.10     Tax Consequences...............................................................................10

         1.11     Accounting Treatment...........................................................................10

         1.12     Further Action.................................................................................10

SECTION 2. REPRESENTATIONS AND WARRANTIES OF THE COMPANY.........................................................10

         2.1      Due Organization; Subsidiaries; Etc............................................................11

         2.2      Certificate of Incorporation and Bylaws; Records...............................................11

         2.3      Capitalization, Etc............................................................................12

         2.4      Financial Statements...........................................................................13

         2.5      Absence of Changes.............................................................................14

         2.6      Title to Assets................................................................................16

         2.7      Bank Accounts; Receivables.....................................................................16

         2.8      Equipment; Leasehold...........................................................................17

         2.9      Proprietary Assets.............................................................................17

         2.10     Contracts......................................................................................20

         2.11     Liabilities....................................................................................23

         2.12     Compliance with Legal Requirements.............................................................23

         2.13     Governmental Authorizations and Facility Certifications........................................23

         2.14     Tax Matters....................................................................................24

         2.15     Employee and Labor Matters; Benefit Plans......................................................25

         2.16     Environmental Matters..........................................................................28
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         2.17     Insurance......................................................................................29

         2.18     Related Party Transactions.....................................................................29

         2.19     Legal Proceedings; Orders......................................................................29

         2.20     Authority; Binding Nature of Agreement.........................................................30

         2.21     Non-Contravention; Consents....................................................................30

         2.22     Inapplicability of Section 2115 of California Corporations Code................................31

         2.23     Vote Required..................................................................................31

         2.24     Brokers or Finders.............................................................................31

         2.25     Full Disclosure................................................................................31

SECTION 3. REPRESENTATIONS AND WARRANTIES OF PARENT AND MERGER SUB...............................................32

         3.1      Organization and Standing; Articles and Bylaws.................................................32

         3.2      Capitalization.................................................................................32

         3.3      Financial Statements...........................................................................33

         3.4      Actions........................................................................................33

         3.5      Title to Properties and Assets; Liens, etc.....................................................34

         3.6      Patents, Trademarks, etc.......................................................................34

         3.7      Proprietary Information and Inventions Agreements..............................................34

         3.8      Material Contracts and Commitments.............................................................34

         3.9      Compliance with Other Instruments..............................................................35

         3.10     Validity of Parent Capital Stock...............................................................35

         3.11     Governmental Authorizations....................................................................35

         3.12     Tax Returns and Payments.......................................................................36

         3.13     Tax Elections..................................................................................36

         3.14     Employees......................................................................................36

         3.15     Employee Benefit Plans.........................................................................36

         3.16     Environmental Matters..........................................................................36

         3.17     Insurance......................................................................................36

         3.18     No Conflict of Interest........................................................................37

         3.19     Litigation, etc................................................................................37

         3.20     Authority; Binding Nature of Agreement.........................................................37
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         3.21     Non-Contravention; Consents....................................................................37

         3.22     Financial Condition............................................................................38

         3.24     U.S. Real Property Holding Corporation.........................................................38

         3.25     Investment Company Act.........................................................................38

         3.26     No Brokers or Finders..........................................................................38

         3.27     Full Disclosure................................................................................38

SECTION 4. CERTAIN COVENANTS OF THE PARTIES......................................................................38

         4.1      Access and Investigation.......................................................................38

         4.2      Operation of the Company's Business............................................................39

         4.3      Notification; Updates to Company Disclosure Schedule...........................................41

         4.4      Notification; Updates to Parent Disclosure Schedule............................................42

         4.5      Operation of Parent's Business.  During the Pre-Closing Period:................................43

         4.6      No Negotiation.................................................................................44

SECTION 5. ADDITIONAL COVENANTS OF THE PARTIES...................................................................44

         5.1      Filings and Consents...........................................................................44

         5.2      Company Stockholders' Meeting..................................................................44

         5.3      Public Announcements...........................................................................45

         5.4      Reasonable Efforts.............................................................................45

         5.5      Tax Matters....................................................................................45

         5.6      Noncompetition Agreements......................................................................46

         5.7      Employment Agreements..........................................................................46

         5.8      Releases.......................................................................................46

         5.9      Underwriter Lockup Agreements..................................................................46

         5.10     Amendment/Clarification of Existing Agreements; Payoff of Company Line of Credit...............46

         5.11     Termination of Certain Agreements..............................................................47

         5.12     FIRPTA Matters.................................................................................47

         5.13     Employee and Related Matters...................................................................47

SECTION 6. CONDITIONS PRECEDENT TO OBLIGATIONS OF PARENT AND MERGER SUB..........................................48

         6.1      Accuracy of Representations....................................................................48
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         6.2      Performance of Covenants.......................................................................48

         6.3      Stockholder Approval...........................................................................48

         6.4      Consents.......................................................................................48

         6.5      Agreements and Documents.......................................................................48

         6.6      Absence of Material Adverse Effect.............................................................49

         6.7      HSR Act........................................................................................49

         6.8      FIRPTA Compliance..............................................................................50

         6.9      No Restraints..................................................................................50

         6.10     No Legal Proceedings...........................................................................50

         6.11     Employees......................................................................................50

         6.12     Termination of Certain Agreements..............................................................50

         6.13     Closing of Series C Investment.................................................................50

         6.15     Company Amended and Restated Certificate.......................................................50

SECTION 7. CONDITIONS PRECEDENT TO OBLIGATIONS OF THE COMPANY....................................................50

         7.1      Accuracy of Representations....................................................................51

         7.2      Performance of Covenants.......................................................................51

         7.3      Documents......................................................................................51

         7.4      No Restraints..................................................................................51

         7.5      Absence of Material Adverse Effect.............................................................51

         7.6      HSR Act........................................................................................51

         7.7      Amended and Restated Certificate...............................................................52

         7.8      Director Appointment...........................................................................52

         7.9      Company Amended and Restated Certificate.......................................................52

SECTION 8. TERMINATION...........................................................................................52

         8.1      Termination Events.............................................................................52

         8.2      Termination Procedures.........................................................................53

         8.3      Effect of Termination..........................................................................53

SECTION 9. INDEMNIFICATION, ETC..................................................................................53

         9.1      Survival of Representations, Etc...............................................................53

         9.2      Indemnification................................................................................54
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         9.3      Deductible.....................................................................................55

         9.4      Exclusive Remedy for Monetary Damages..........................................................55

         9.5      No Contribution................................................................................56

         9.6      Interest.......................................................................................56

         9.7      Defense of Third Party Claims..................................................................56

         9.8      Exercise of Remedies by Parent Indemnitees Other Than Parent...................................57

SECTION 10. MISCELLANEOUS PROVISIONS.............................................................................57

         10.1     Stockholders' Agents...........................................................................57

         10.2     Further Assurances.............................................................................57

         10.3     Fees and Expenses..............................................................................57

         10.4     Attorneys' Fees................................................................................57

         10.5     Notices........................................................................................57

         10.6     Confidentiality................................................................................59

         10.7     Time of the Essence............................................................................59

         10.8     Headings.......................................................................................59

         10.9     Counterparts...................................................................................59

         10.10    Governing Law..................................................................................59

         10.11    Successors and Assigns.........................................................................59

         10.12    Remedies Cumulative; Specific Performance......................................................59

         10.13    Waiver.........................................................................................60

         10.14    Amendments.....................................................................................60

         10.15    Severability...................................................................................60

         10.16    Parties in Interest............................................................................60

         10.17    Entire Agreement...............................................................................60

         10.18    Construction...................................................................................60
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                                       v.
<PAGE>


                               AGREEMENT AND PLAN
                          OF MERGER AND REORGANIZATION

       THIS AGREEMENT AND PLAN OF MERGER AND REORGANIZATION ("Agreement") is
made and entered into as of December 17, 2000, by and among: DNA SCIENCES, INC.,
a Delaware corporation ("Parent"), PIPO ACQUISITION CORP., a Delaware
corporation and a wholly owned subsidiary of Parent ("Merger Sub"), and PPGX,
INC., a Delaware corporation (the "Company"). Certain capitalized terms used in
this Agreement are defined in EXHIBIT A.

                                    RECITALS

       A.     Parent, Merger Sub and the Company intend to effect a merger of
Merger Sub into the Company in accordance with this Agreement and the Delaware
General Corporation Law (the "Merger"). Upon consummation of the Merger, Merger
Sub will cease to exist, and the Company will become a wholly owned subsidiary
of Parent.

       B.     It is intended that the Merger qualify as a tax-free
reorganization within the meaning of Section 368(a) of the Internal Revenue Code
of 1986, as amended (the "Code"). For accounting purposes, it is intended that
the Merger be treated as a "purchase."

       C.     This Agreement has been approved by the respective boards of
directors of Parent, Merger Sub and the Company.

       D.     Contemporaneously with the execution and delivery of this
Agreement, each of Axys Pharmaceuticals, Inc. ("Axys") and Pharmaceutical
Product Development, Inc. ("PPD," and collectively with Axys, the "Major
Stockholders") is executing and delivering to Parent a voting agreement (a
"Voting Agreement") of even date herewith substantially in the form of EXHIBIT
B.

                                    AGREEMENT

       The parties to this Agreement agree as follows:

SECTION 1. DESCRIPTION OF TRANSACTION

       1.1    MERGER OF MERGER SUB INTO THE COMPANY. Upon the terms and subject
to the conditions set forth in this Agreement, at the Effective Time (as defined
in Section 1.3), Merger Sub shall be merged with and into the Company, and the
separate existence of Merger Sub shall cease. The Company will continue as the
surviving corporation in the Merger (the "Surviving Corporation").

       1.2    EFFECT OF THE MERGER. The Merger shall have the effects set forth
in this Agreement and in the applicable provisions of the Delaware General
Corporation Law.

       1.3    CLOSING; EFFECTIVE TIME. The consummation of the transactions
contemplated by this Agreement (the "Closing") shall take place at the offices
of Cooley Godward LLP, 3000 El Camino Real, Five Palo Alto Square, Palo Alto,
California 94306 at 10:00 a.m. on a date to be


                                       1.
<PAGE>

mutually agreed upon by Parent and the Company no later than three days after
the satisfaction (or, to the extent permitted, the waiver) of the conditions set
forth in Sections 6 and 7. Contemporaneously with or as promptly as practicable
after the Closing, a properly executed certificate of merger conforming to the
requirements of the Delaware General Corporation Law shall be filed with the
Secretary of State of the State of Delaware. The Merger shall become effective
at the time such certificate of merger is filed with the Secretary of State of
the State of Delaware (the "Effective Time").

       1.4    CERTIFICATE OF INCORPORATION AND BYLAWS; DIRECTORS AND OFFICERS.
Unless otherwise determined by Parent and the Company prior to the Effective
Time:

              (a)    the certificate of incorporation of the Surviving
       Corporation shall be amended and restated as of the Effective Time in a
       form acceptable to Parent;

              (b)    the bylaws of the Surviving Corporation shall be amended
       and restated as of the Effective Time to conform to the bylaws of Merger
       Sub as in effect immediately prior to the Effective Time; and

              (c)    the directors and officers of the Surviving Corporation
       immediately after the Effective Time shall be the individuals selected by
       Parent prior to the Closing.

       1.5    CONVERSION OF SHARES.

              (a)    Subject to Sections 1.8(c) and 1.9, at the Effective Time,
by virtue of the Merger and without any further action on the part of Parent,
Merger Sub, the Company or any stockholder of the Company:

                     (i)    each share of common stock of the Company (par value
       $0.001 per share) ("Company Common Stock") outstanding immediately prior
       to the Effective Time shall be converted into the right to receive a
       fraction of a share of the common stock (par value $0.001 per share) of
       Parent ("Parent Common Stock") equal to the Remainder Exchange Ratio;

                     (ii)   each share of Series A preferred stock of the
       Company (par value $0.001 per share) ("Company Series A Preferred Stock")
       outstanding immediately prior to the Effective Time shall be converted
       into the right to receive a fraction of a share of the Series D preferred
       stock (par value $0.001 per share) of Parent ("Parent Series D Preferred
       Stock," and together with Parent Common Stock, "Parent Capital Stock")
       equal to the Series A Exchange Ratio; and

                     (iii)  each share of the common stock (par value $0.001 per
       share) of Merger Sub outstanding immediately prior to the Effective Time
       shall be converted into one share of common stock of the Surviving
       Corporation.

              (b)    For purposes of this Agreement:


                                       2.
<PAGE>

              (i)    The "Series A Exchange Ratio" shall be equal to (A) the
       Liquidation Portion Exchange Ratio PLUS (B) the Remainder Exchange Ratio,
       rounded to five decimal places.

              (ii)   The "Liquidation Consideration" shall be equal to (A) the
       Debt Repayment DIVIDED BY (B) a fraction, the numerator of which is
       $47,000,000, and the denominator of which is the Merger Consideration,
       rounded to five decimal places.

              (iii)  The "Liquidation Portion Exchange Ratio" is equal to (A)
       the Liquidation Consideration DIVIDED BY (B) 10,000,000, rounded to five
       decimal places.

              (iv)   The "Remainder Exchange Ratio" shall be equal to (A) the
       Merger Consideration MINUS the Liquidation Consideration DIVIDED BY (B)
       the Aggregate Company Common Number, rounded to five decimal places.

              (v)    The "Debt Repayment" shall mean (A) the actual outstanding
       indebtedness due and payable to the Bank (as defined in Section 4.2(k))
       that is actually repaid by the Company on or prior to the Closing Date in
       accordance with Section 5.10(c) and (B) the value of the indebtedness due
       and payable to the Major Stockholders under the Loan Agreement (as
       defined in Section 4.2(n)) that is actually contributed to capital of the
       Company by the Major Stockholders on or prior to the Closing Date in
       accordance with Section 5.10(c).

              (vi)   "Merger Consideration" shall be equal to (A) 0.1175 TIMES
       (B) the Aggregate Parent Common Number.

              (vii)  The "Aggregate Parent Common Number" shall mean the sum of
       (1) the total number of shares of Parent Common Stock that are issued and
       outstanding on the date hereof; (2) the total number of shares of Parent
       Common Stock that are issuable upon the conversion of any shares of
       Parent Preferred Stock issued and outstanding on the date hereof; (3) the
       total number of shares of Parent Common Stock that are issuable upon the
       conversion of any shares of Parent Series C Preferred Stock issued to PPD
       in connection with the closing of the Series C Investment (as defined in
       Section 6.14) and issued or to be issued to Alliance Capital Partners;
       (4) the total number of shares of Parent Common Stock that are issuable
       upon the exercise in full of all warrants to acquire shares of Parent
       Common Stock that are outstanding on the date hereof; (5) the total
       number of shares of Parent Common Stock that are issuable upon conversion
       of any shares of Parent Preferred Stock that are issuable upon the
       exercise in full of all warrants to acquire shares of Parent Preferred
       Stock that are outstanding on the date hereof; (6) the total number of
       shares of Down Round Stock that are issued and outstanding immediately
       prior to the Effective Time or pursuant to a contractual agreement under
       which Parent is bound, as of the Effective Time, to issue Down Round
       Stock subsequent to the Effective Time; and (7) the total number of
       shares of capital stock of Parent that are issuable upon the conversion
       or exercise in full of all convertible securities or options (whether
       vested or unvested), warrants or other rights to acquire capital stock of
       Parent that are outstanding on the Initial Series C Closing Date other
       than


                                       3.
<PAGE>

       convertible securities or warrants referred to in clauses "(2)," "(3),"
       "(4)," "(5)" or "(6)" of this sentence; PROVIDED, HOWEVER, that
       notwithstanding anything to the contrary contained in this paragraph, no
       shares, warrants, options or rights shall be counted more than one time
       in calculating the "Aggregate Parent Common Number."

              (viii) The "Aggregate Company Common Number" shall mean the sum of
       (1) the total number of shares of Company Common Stock that are issued
       and outstanding immediately prior to the Effective Time; (2) the total
       number of shares of Company Common Stock that are issuable upon the
       conversion of any shares of Company Series A Preferred Stock issued and
       outstanding immediately prior to the Effective Time; and (3) the total
       number of shares of Company Capital Stock that are issuable upon the
       conversion or exercise in full of all convertible securities or options,
       warrants or other rights to acquire capital stock of the Company that are
       outstanding immediately prior to the Effective Time other than
       convertible securities or warrants referred to in clause "(2)" of this
       sentence; PROVIDED, HOWEVER, that notwithstanding anything to the
       contrary contained in this paragraph, no shares, warrants, options or
       rights shall be counted more than one time in calculating the "Aggregate
       Company Common Number."

              (ix)   "Down Round Stock" shall mean all shares of Parent Common
       Stock issued or deemed to be issued by Parent pursuant to this Section
       1.5(b)(v) in a Subsequent Equity Financing (as defined in Section
       1.5(b)(ix)) after the date hereof for an Effective Price less than $14.27
       other than (A) shares of Parent Common Stock issued upon conversion of
       Parent Preferred Stock; (B) shares of Parent Common Stock issued pursuant
       to the bona fide acquisition of (i) another entity by Parent by merger,
       purchase of substantially all of the assets of such entity, or other
       reorganization, or (ii) technology, software, patents or other
       intellectual property by license or purchase; (C) up to 4,500,000 shares
       of Parent Common Stock (or related options) issued to employees,
       officers, directors, consultants, or other persons performing services
       for Parent (including, but not by way of limitation, distributors and
       sales representatives) pursuant to any stock offering, plan, or
       arrangement approved by Parent's board of directors; (D) shares of
       capital stock issued to financial institutions in connection with the
       extension of credit to Parent or in connection with the lease of
       equipment, up to a maximum of one percent (1%) of Parent Common Stock
       issued and outstanding immediately prior to the date of this Agreement,
       and in both cases for other than equity financing purposes as approved by
       Parent's board of directors; or (E) shares of capital stock issued in
       connection with any stock split, stock dividend or recapitalization by
       Parent. In the event Parent at any time or from time to time after the
       date of this Agreement issues any Options or Convertible Securities or
       shall fix a record date for the determination of holders of any class of
       securities entitled to receive any such Options or Convertible
       Securities, then the maximum number of shares (as set forth in the
       instrument relating thereto assuming the satisfaction of any conditions
       to exercisability, including, without limitation, the passage of time and
       without regard to any provisions contained therein for a subsequent
       adjustment of such number) of Parent Common Stock issuable upon the
       exercise of such Options or, in the case of Convertible Securities and
       Options therefor, the conversion or exchange of such Convertible
       Securities, shall be deemed to be shares


                                       4.
<PAGE>

       of Down Round Stock issued as of the time of such issue or, in case such
       a record date shall have been fixed, as of the close of business on such
       record date, provided that with respect to a series of preferred stock of
       Parent, Down Round Stock shall not be deemed to have been issued unless
       the consideration per share of such Down Round Stock would be less than
       the conversion price of such series in effect on the date of and
       immediately prior to such issue, or such record date, as the case may be,
       and provided further that in any such case in which shares of Down Round
       Stock are deemed to be issued:

              (1)    no further adjustment in the Aggregate Parent Common Number
shall be made upon the subsequent issue of Convertible Securities or shares of
Parent Common Stock upon the exercise of such Options or conversion or exchange
of such Convertible Securities;

              (2)    if such Options or Convertible Securities by their terms
provide, with the passage of time or otherwise, for any increase or decrease in
the consideration payable to Parent, or in the number of shares of Parent Common
Stock issuable, upon the exercise, conversion or exchange thereof, the Exchange
Ratio shall be computed so as to reflect any such increase or decrease that has
occurred on or prior to the Effective Time insofar as it affects such Options or
the rights of conversion or exchange under such Convertible Securities;

              (3)    in the event of the expiration or termination of any such
Options or any rights of conversion or exchange under such Convertible
Securities on or prior to the Effective Time, the Exchange Ratio shall be
computed as if:

                     a.     in the case of Convertible Securities or Options for
              Parent Common Stock, the only shares of Down Round Stock issued
              were shares of Parent Common Stock, if any, actually issued upon
              the exercise of such Options or the conversion or exchange of such
              Convertible Securities and the consideration received therefor was
              the consideration actually received by Parent for the issue of all
              such Options, whether or not exercised, plus the consideration
              actually received by Parent upon such exercise, or for the issue
              of all such Convertible Securities which were actually converted
              or exchanged, plus the additional consideration, if any, actually
              received by Parent upon such conversion or exchange, and

                     b.     in the case of Options for Convertible Securities,
              only the Convertible Securities, if any, actually issued upon the
              exercise thereof were issued at the time of issue of such Options,
              and the consideration received by Parent for the shares of Down
              Round Stock deemed to have been then issued was the consideration
              actually received by Parent for the issue of all such Options,
              whether or not exercised, plus the consideration deemed to have
              been received by Parent upon the issue of the Convertible
              Securities with respect to which such Options were actually
              exercised;


                                       5.
<PAGE>

                     (x)    "Convertible Securities" shall mean any evidences of
       indebtedness, shares (other than Parent Common Stock) or other securities
       convertible into or exchangeable for Parent Common Stock.

                     (xi)   The "Effective Price" of a share of Down Round Stock
       shall mean the quotient obtained by dividing the total number of shares
       of Down Round Stock issued or sold, or deemed to have been issued or sold
       by Parent under Section 1.5(b)(v), into the dollar value of the aggregate
       consideration received, or deemed to have been received by Parent, for
       such shares of Down Round Stock.

                     (xii)  "Options" shall mean rights, options or warrants to
       subscribe for, purchase or otherwise acquire either Parent Common Stock
       or Convertible Securities.

                     (xiii) A "Subsequent Equity Financing" shall mean the sale
       by Parent, prior to the Effective Time, of Down Round Stock.

              (c)    If any shares of Company Capital Stock outstanding
immediately prior to the Effective Time are unvested or are subject to a
repurchase option, risk of forfeiture or other condition under any applicable
restricted stock purchase agreement or other agreement with the Company, then
the shares of Parent Capital Stock issued in exchange for such shares of Company
Capital Stock will also be unvested and subject to the same repurchase option,
risk of forfeiture or other condition, and the certificates representing such
shares of Parent Capital Stock may accordingly be marked with appropriate
legends.

              (d)    Fifteen percent (15%) of the shares of Parent Capital Stock
otherwise issuable in the Merger to the Major Stockholders (without taking into
account any deductions in respect of payment for Excess Transaction Expenses)
shall be delivered into escrow and held as specified in Section 1.8. In
addition, to the extent a Major Stockholder has not paid such Major
Stockholder's pro rata portion of the Excess Transaction Expenses, an additional
number of shares of Parent Series D Preferred Stock equal to the quotient
obtained by dividing (1) such Major Stockholder's pro rata portion of such
Excess Transaction Expenses by (2) $14.27 (rounded down to the nearest whole
number of shares) shall be deducted from the number of shares of Parent Series D
Preferred Stock otherwise issuable to such Major Stockholder.

              (e)    If, between the date of this Agreement and the Effective
Time, the outstanding shares of Company Capital Stock or Parent Capital Stock
are changed into a different number or class of shares by reason of any stock
split, division or subdivision of shares, stock dividend, reverse stock split,
consolidation of shares, reclassification, recapitalization or other similar
transaction, then the Exchange Ratio shall be appropriately adjusted.

       1.6    STOCK OPTIONS. At the Effective Time, each option to purchase
shares of Company Capital Stock that is then outstanding, whether vested or
unvested (a "Company Option"), shall be assumed by Parent in accordance with the
terms (as in effect as of the date of this Agreement) of the Company's 1999
Equity Incentive Plan (the "Stock Plan") and the stock option agreement by which
such Company Option is evidenced. All rights with respect to Company Common
Stock under outstanding Company Options shall thereupon be converted into


                                       6.
<PAGE>

rights with respect to Parent Common Stock. Accordingly, from and after the
Effective Time, (i) each Company Option assumed by Parent may be exercised
solely for shares of Parent Common Stock, (ii) the number of shares of Parent
Common Stock subject to each such assumed Company Option shall be equal to the
number of shares of Company Common Stock that were subject to such Company
Option immediately prior to the Effective Time multiplied by the Exchange Ratio,
rounded down to the nearest whole number of shares of Parent Common Stock, (iii)
the per share exercise price for the Parent Common Stock issuable upon exercise
of each such assumed Company Option shall be determined by dividing the exercise
price per share of Company Common Stock subject to such Company Option, as in
effect immediately prior to the Effective Time, by the Exchange Ratio, and
rounding the resulting exercise price up to the nearest whole cent and (iv) all
restrictions on the exercise of each such assumed Company Option shall continue
in full force and effect, and the term, exercisability, vesting schedule and
other provisions of such Company Option shall otherwise remain unchanged and
shall continue to have, and be subject to, the same terms and conditions as set
forth in the Stock Plan and/or stock option agreement by which such Company
Option is evidenced immediately prior to the Effective Time; PROVIDED, HOWEVER,
that each such assumed Company Option shall, in accordance with its terms, be
subject to further adjustment as appropriate to reflect any stock split, reverse
stock split, stock dividend, recapitalization or other similar transaction
effected by Parent after the Effective Time. The Company and Parent shall take
all action that may be necessary to effectuate the provisions of this Section
1.6. Following the Closing, Parent will send to each holder of an assumed
Company Option a written notice setting forth (i) the number of shares of Parent
Common Stock subject to such assumed Company Option, and (ii) the exercise price
per share of Parent Common Stock issuable upon exercise of such assumed Company
Option. Parent shall take all necessary corporate action to reserve for issuance
a sufficient number of shares of Parent Common Stock for delivery upon exercise
of Company Options assumed in accordance with this Section 1.6. Notwithstanding
anything to the contrary contained in this Section 1.6, in lieu of assuming
outstanding Company Options in accordance with this Section 1.6 Parent may, at
its election, cause such outstanding Company Options to be replaced by issuing
reasonably equivalent replacement stock options in substitution therefor.

       1.7    CLOSING OF THE COMPANY'S TRANSFER BOOKS. At the Effective Time,
holders of certificates representing shares of Company Capital Stock that were
outstanding immediately prior to the Effective Time shall cease to have any
rights as stockholders of the Company, and the stock transfer books of the
Company shall be closed with respect to all shares of such capital stock
outstanding immediately prior to the Effective Time. No further transfer of any
such shares of Company Capital Stock shall be made on such stock transfer books
after the Effective Time. If, after the Effective Time, a valid certificate
previously representing any of such shares of Company Capital Stock (a "Company
Stock Certificate") is presented to the Surviving Corporation or Parent, such
Company Stock Certificate shall be canceled and shall be exchanged as provided
in Section 1.8.

       1.8    EXCHANGE OF CERTIFICATES; ESCROW SHARES.

              (a)    At or prior to the Effective Time, Parent shall reserve for
exchange in accordance with this Section 1, (i) the aggregate number of shares
of Parent Capital Stock issuable pursuant to Section 1.5 in exchange for
outstanding shares of Company Capital Stock



                                       7.
<PAGE>

and (ii) cash for fractional shares in the amount described in Section 1.8(c).
At the Closing, each Company stockholder that does not perfect its appraisal
rights and is otherwise entitled to receive shares of Parent Capital Stock
pursuant to Section 1.5 (a "Merger Stockholder") shall surrender to Parent all
certificates representing shares of Company Capital Stock (properly endorsed for
transfer). At or as soon as practicable after the Effective Time, Parent shall
(i) deliver to each Merger Stockholder that is not a Major Stockholder
certificates representing one hundred percent (100%) of the number of whole
shares of Parent Common Stock and/or Parent Series D Preferred Stock, as the
case may be, that such Merger Stockholder has the right to receive pursuant to
the provisions of Section 1.5 (ii) deliver to each Major Stockholder
certificates representing eighty-five percent (85%) of the number of whole
shares of Parent Common Stock and/or Parent Series D Preferred Stock, as the
case may be, that such Merger Stockholder has the right to receive pursuant to
the provisions of Section 1.5 and (ii) deliver to the escrow agent under the
Escrow Agreement in the form of EXHIBIT C hereto (the "Escrow Agreement"), on
behalf and in the name of each Major Stockholder, certificates representing
fifteen percent (15%) of the number of whole shares of Parent Common Stock
and/or Parent Series D Preferred Stock, as the case may be, that such Major
Stockholder has the right to receive pursuant to the provisions of Section 1.5
(the "Escrow Shares"). If any Company Stock Certificate shall have been lost,
stolen or destroyed, Parent may, in its discretion and as a condition precedent
to the issuance of any certificate representing Parent Capital Stock, require
the owner of such lost, stolen or destroyed Company Stock Certificate to provide
an appropriate affidavit and indemnity agreement against any claim that may be
made against Parent or the Surviving Corporation with respect to such Company
Stock Certificate.

              (b)    No dividends or other distributions declared or made with
respect to Parent Capital Stock with a record date after the Effective Time
shall be paid to the holder of any unsurrendered Company Stock Certificate with
respect to the shares of Parent Common Stock or Parent Series D Preferred Stock
represented thereby, and no cash payment in lieu of any fractional share shall
be paid to any such holder, until such holder surrenders such Company Stock
Certificate in accordance with this Section 1.8 or delivers the affidavit and
indemnity agreement referred to in Section 1.8(a) (at which time such holder
shall be entitled receive all such dividends and distributions and such cash
payment).

              (c)    No fractional shares of Parent Capital Stock shall be
issued in connection with the Merger, and no certificates for any such
fractional shares shall be issued. In lieu of such fractional shares, any holder
of Company Capital Stock who would otherwise be entitled to receive a fraction
of a share of Parent Common Stock (after aggregating all fractional shares of
Parent Common Stock issuable to such holder) and/or a fraction of a share of
Parent Series D Preferred Stock (after aggregating all fractional shares of
Parent Series D Preferred Stock issuable to such holder) shall, upon surrender
of such holder's Company Stock Certificate(s) or affidavit and indemnity
agreement referred to in Section 1.8(a), as the case may be, be paid in cash the
dollar amount (rounded to the nearest whole cent), without interest, determined
by multiplying such fraction by (i) $2.05, with respect to a fraction of a share
of Parent Common Stock, and (b) $14.27, with respect to a fraction of a share of
Parent Series D Preferred Stock.

              (d)    The shares of Parent Capital Stock to be issued in the
Merger shall be characterized as "restricted securities" for purposes of Rule
144 under the Securities Act, and


                                       8.
<PAGE>

each certificate representing any such shares shall, until such time that the
shares are not so restricted under the Securities Act, bear a legend identical
or similar in effect to the following legend (together with any other legend or
legends required by applicable state securities laws or otherwise, if any):

                     "THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
              REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE "ACT") AND MAY
              NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED, ASSIGNED, PLEDGED
              OR HYPOTHECATED UNLESS REGISTERED UNDER THE ACT OR UNLESS AN
              EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE ACT IS
              AVAILABLE."

              (e)    Parent and the Surviving Corporation shall be entitled to
deduct and withhold from any consideration payable or otherwise deliverable to
any holder or former holder of Company Capital Stock pursuant to this Agreement
such amounts as Parent or the Surviving Corporation may be required to deduct or
withhold therefrom under the Code or under any provision of state, local or
foreign tax law. To the extent such amounts are so deducted or withheld, such
amounts shall be treated for all purposes under this Agreement as having been
paid to the Person to whom such amounts would otherwise have been paid.

              (f)    Neither Parent nor the Surviving Corporation shall be
liable to any holder or former holder of Company Capital Stock for any shares of
Parent Capital Stock (or dividends or distributions with respect thereto), or
for any cash amounts, delivered to any public official pursuant to any
applicable abandoned property, escheat or similar law.

              (g)    The Escrow Shares shall be maintained in an escrow fund
(the "Escrow Fund") for purposes of satisfying claims brought pursuant to
Section 9 and for the period of time set forth in the Escrow Agreement.






                                       9.
<PAGE>

     1.9  APPRAISAL RIGHTS.

          (a) Notwithstanding anything to the contrary contained in this
Agreement, any shares of Company Capital Stock for which, as of the Effective
Time, the holder thereof has demanded an appraisal of their value in accordance
with Section 262 of the Delaware General Corporation Law ("Dissenting Shares")
shall not be converted into or represent the right to receive Parent Capital
Stock in accordance with Section 1.5, and the holder or holders of such shares
shall be entitled only to such rights as may be granted to such holder or
holders in Section 262 of the Delaware General Corporation Law; PROVIDED,
HOWEVER, that if the status of any such shares as Dissenting Shares shall not be
perfected in accordance with Section 262 of the Delaware General Corporation
Law, or if any such shares shall lose their status as Dissenting Shares then, as
of the later of the Effective Time or the time of the failure to perfect such
status or the loss of such status, such shares shall automatically be converted
into and shall represent only the right to receive (upon the surrender of the
certificate or certificates representing such shares) Parent Capital Stock in
accordance with Section 1.5.

          (b) The Company shall give Parent (i) prompt notice of any written
demand received by the Company at or prior to any meeting of the Company's
stockholders pursuant to Section 5.2 hereof to require the Company to purchase
Dissenting Shares pursuant to Section 262 of the Delaware General Corporation
Law and of any other demand, notice or instrument delivered to the Company prior
to the Effective Time pursuant to the Delaware General Corporation Law, and (ii)
the opportunity to participate in all negotiations and proceedings with respect
to any such demand, notice or instrument. The Company shall not make any payment
or settlement offer prior to the Effective Time with respect to any such demand
unless Parent shall have consented in writing to such payment or settlement
offer.

     1.10 TAX CONSEQUENCES. For federal income tax purposes, the Merger is
intended to constitute a reorganization within the meaning of Section 368 of the
Code. The parties to this Agreement hereby adopt this Agreement as a "plan of
reorganization" within the meaning of Sections 1.368-2(g) and 1.368-3(a) of the
United States Treasury Regulations.

     1.11 ACCOUNTING TREATMENT. For accounting purposes, the Merger is
intended to be treated as a "purchase."

     1.12 FURTHER ACTION. If, at any time after the Effective Time, any
further action is determined by Parent to be necessary or desirable to carry out
the purposes of this Agreement or to vest the Surviving Corporation or Parent
with full right, title and possession of and to all rights and property of
Merger Sub and the Company, the officers and directors of the Surviving
Corporation and Parent shall be fully authorized (in the name of Merger Sub, in
the name of the Company and otherwise) to take such action.

SECTION 2.  REPRESENTATIONS AND WARRANTIES OF THE COMPANY

          Except as set forth in the Company Disclosure Schedule, which shall be
arranged in paragraphs corresponding to the numbered and lettered paragraphs
contained in this Section 2,


                                       10.
<PAGE>

the Company represents and warrants, to and for the benefit of the Parent
Indemnitees, as follows:

     2.1 DUE ORGANIZATION; SUBSIDIARIES; ETC.

          (a) The Company has no Subsidiaries, except for the Entities
identified in Part 2.1(a)(i) of the Company Disclosure Schedule; and neither the
Company nor any of the other Entities identified in Part 2.1(a)(i) of the
Company Disclosure Schedule owns any capital stock of, or any equity interest of
any nature in, any other Entity, other than the Entities identified in Part
2.1(a)(ii) of the Company Disclosure Schedule. (The Company and each of its
Subsidiaries are referred to collectively in this Agreement as the "Acquired
Corporations.") Except as set forth in Part 2.1(a)(iii) of the Company
Disclosure Schedule, none of the Acquired Corporations has agreed or is
obligated to make, or is bound by any Contract under which it may become
obligated to make, any future investment in or capital contribution to any other
Entity. Except as set forth in Part 2.1(a)(iv) of the Company Disclosure
Schedule, none of the Acquired Corporations has, at any time, been a general
partner of, or has otherwise been liable for any of the debts or other
obligations of, any general partnership, limited partnership or other Entity.

          (b) Each of the Acquired Corporations is a corporation duly organized,
validly existing and in good standing under the laws of the jurisdiction of its
incorporation and has all necessary power and authority: (i) to conduct its
business in the manner in which its business is currently being conducted; (ii)
to own and use its assets in the manner in which its assets are currently owned
and used; and (iii) to perform its obligations under all Contracts by which it
is bound.

          (c) Each of the Acquired Corporations is qualified to do business as a
foreign corporation, and is in good standing, under the laws of all
jurisdictions where the nature of its business requires such qualification and
where the failure to be so qualified would reasonably be expected to have a
Material Adverse Effect on such Acquired Corporation. Part 2.1(c) of the Company
Disclosure Schedule accurately sets forth for each of the respective Acquired
Corporations each jurisdiction where such qualification is required.

          (d) Except as set forth in Part 2.1(d) of the Company Disclosure
Schedule, the Company has not conducted any business under or otherwise used,
for any purpose or in any jurisdiction, any fictitious name, assumed name, trade
name or other name, other than the name "PPGx, Inc."

          (e) Part 2.1(e) of the Company Disclosure Schedule accurately sets
forth for each of the respective Acquired Corporations: (i) the names of the
members of the board of directors, (ii) the names of the members of each
committee of the board of directors, and (iii) the names and titles of each of
the officers.

     2.2 CERTIFICATE OF INCORPORATION AND BYLAWS; RECORDS. The Company has
delivered to Parent accurate and complete copies of: (1) the certificate of
incorporation, bylaws and other charter or similar organizational documents of
the respective Acquired Corporations, including all amendments thereto; (2)
stock records of each of the Acquired Corporations; and (3) except


                                       11.
<PAGE>

as set forth in Part 2.2 of the Company Disclosure Schedule, the minutes and
other records of the meetings and other proceedings (including any actions taken
by written consent or otherwise without a meeting) of the stockholders, the
board of directors and all committees of the board of directors of each of the
Acquired Corporations. The stockholders and board of directors of the Company
have ratified, confirmed and approved all prior lawful action taken on behalf of
the Company by the Company's board of directors (in the case of ratification,
confirmation and approval by the Company's stockholders) and the Company's
officers (in the case of ratification, confirmation and approval by the
Company's board of directors). There has not been any violation of any of the
provisions of the certificate of incorporation, bylaws or other charter or
similar organizational documents of any of the Acquired Corporations, and none
of the Acquired Corporations has taken any action that is inconsistent in any
material respect with any resolution adopted by its stockholders, board of
directors or any committee of its board of directors. The books of account,
stock records, minute books and other records of each of the Acquired
Corporations are accurate, up-to-date and complete in all material respects, and
have been maintained in accordance with prudent business practices.

     2.3 CAPITALIZATION, ETC.

          (a) As of the date of this Agreement, the authorized capital stock of
the Company consists of: (i) 15,000,000 shares of Company Common Stock, of which
29,000 shares have been issued and are outstanding; and (ii) 10,000,000 shares
of preferred stock (par value $0.001 per share), all of which have been
designated "Series A Preferred Stock," of which 10,000,000 shares have been
issued and are outstanding as of the date of this Agreement. Each outstanding
share of preferred stock is convertible into one share of Company Common Stock.
All of the outstanding shares of Company Common Stock and Company Series A
Preferred Stock have been duly authorized and validly issued, and are fully paid
and non-assessable. As of the date of this Agreement, there are no shares of
Company Capital Stock held by any of the other Acquired Corporations. Part
2.3(a) of the Company Disclosure Schedule provides an accurate and complete
description of the terms of each repurchase option which is held by the Company
and to which any of such shares is subject. Except as set forth in Part 2.3(a)
of the Company Disclosure Schedule, there is no Acquired Corporation Contract
relating to the voting or registration of, or restricting any Person from
purchasing, selling, pledging or otherwise disposing of (or granting any option
or similar right with respect to), any shares of Company Capital Stock. None of
the Acquired Corporations is under any obligation, or is bound by any Contract
pursuant to which it may become obligated, to repurchase, redeem or otherwise
acquire any outstanding shares of Company Capital Stock.

          (b) The Company has reserved 1,775,000 shares of Company Common Stock
for issuance under the Stock Plan, of which options to purchase 1,405,900 shares
are outstanding as of the date of this Agreement. Part 2.3(b) of the Company
Disclosure Schedule accurately sets forth, with respect to each Company Option
that is outstanding as of the date of this Agreement: (i) the name of the holder
of such Company Option; (ii) the total number of shares of Company Common Stock
that are subject to such Company Option and the number of shares of Company
Common Stock with respect to which such Company Option is immediately
exercisable; (iii) the date on which such Company Option was granted and the
term of such Company Option; (iv) the vesting schedule for such Company Option;
(v) the exercise price per share of Company


                                       12.
<PAGE>

Common Stock purchasable under such Company Option; and (vi) whether such
Company Option has been designated an "incentive stock option" as defined in
Section 422 of the Code.

          (c) Except as set forth in Part 2.3(b) or Part 2.3(c) of the Company
Disclosure Schedule, there is no: (i) outstanding subscription, option, call,
warrant or right (whether or not currently exercisable) to acquire any shares of
the capital stock or other securities of any of the Acquired Corporations; (ii)
outstanding security, instrument or obligation that is or may become convertible
into or exchangeable for any shares of the capital stock or other securities of
any of the Acquired Corporations; (iii) Contract under which any of the Acquired
Corporations is or may become obligated to sell or otherwise issue any shares of
its capital stock or any other securities; or (iv) to the Knowledge of the
Company, condition or circumstance that may give rise to or provide a basis for
the assertion of a claim by any Person to the effect that such Person is
entitled to acquire or receive any shares of capital stock or other securities
of the Acquired Corporations.

          (d) All outstanding shares of Company Common Stock and Company Series
A Preferred Stock, all outstanding Company Options and all outstanding shares of
capital stock of each Subsidiary of the Company have been issued and granted in
compliance with (i) all applicable securities laws and other applicable Legal
Requirements, and (ii) all requirements set forth in applicable Contracts.

          (e) Except as set forth in Part 2.3(e) of the Company Disclosure
Schedule, the Company has never repurchased, redeemed or otherwise reacquired
any shares of capital stock or other securities of the Company. All securities
so reacquired by the Company were reacquired in compliance with (i) the
applicable provisions of the Delaware General Corporation Law and all other
applicable Legal Requirements, and (ii) all requirements set forth in applicable
restricted stock purchase agreements and other applicable Contracts.

          (f) Except as set forth in Part 2.3(f) of the Company Disclosure
Schedule, all of the outstanding shares of capital stock or other ownership
interests of the Entities identified in Part 2.1(a) of the Company Disclosure
Schedule that have been issued to the Company have been duly authorized and are
validly issued, are fully paid and nonassessable and are owned beneficially and
of record by the Company, free and clear of any Encumbrances.

     2.4 FINANCIAL STATEMENTS.

          (a) The Company has delivered to Parent the following financial
statements and notes (collectively, the "Acquired Corporation Financial
Statements"):

               (i) The audited consolidated balance sheets of the Acquired
Corporations as of December 31, 1999, and the related audited consolidated
income statements, consolidated statements of stockholders' equity and
consolidated statements of cash flows for the Acquired Corporations for the year
then ended, together with the notes thereto and the unqualified report and
opinion of Ernst & Young relating thereto; and

               (ii) the unaudited consolidated balance sheet of the Acquired
Corporations as of September 30, 2000 (the "Unaudited Interim Balance Sheet"),
and the related


                                       13.
<PAGE>

unaudited consolidated income statement of the Acquired Corporations for the
nine months then ended.

          (b) The Acquired Corporation Financial Statements are accurate and
complete in all material respects and present fairly the consolidated financial
position of the Acquired Corporations as of the respective dates thereof and the
consolidated results of operations and (in the case of the financial statements
referred to in Section 2.4(a)(i)) consolidated cash flows of the Acquired
Corporations for the periods covered thereby. The Acquired Corporation Financial
Statements have been prepared in accordance with generally accepted accounting
principles applied on a consistent basis throughout the periods covered (except
that the financial statements referred to in Section 2.4(a)(ii) do not contain
footnotes and are subject to normal and recurring year-end audit adjustments,
which will not, individually or in the aggregate, be material in magnitude).

     2.5 ABSENCE OF CHANGES. Except as set forth in Part 2.5 of the Company
Disclosure Schedule, since September 30, 2000:

          (a) there has not been any material adverse change in the business,
     condition, assets, liabilities, operations or financial performance of the
     Acquired Corporations taken as a whole, and, to the Knowledge of the
     Company, no event has occurred that will, or could reasonably be expected
     to, have a Material Adverse Effect on the Acquired Corporations;

          (b) there has not been any material loss, damage or destruction to, or
     any material interruption in the use of, any of the assets of any of the
     Acquired Corporations (whether or not covered by insurance);

          (c) none of the Acquired Corporations has (i) declared, accrued, set
     aside or paid any dividend or made any other distribution in respect of any
     shares of capital stock, or (ii) repurchased, redeemed or otherwise
     reacquired any shares of capital stock or other securities;

          (d) none of the Acquired Corporations has sold, issued or authorized
     the issuance of (i) any capital stock or other security (except for Company
     Common Stock issued upon the exercise of outstanding Company Options), (ii)
     any option or right to acquire any capital stock or any other security
     (except for Company Options described in Part 2.3(b) of the Company
     Disclosure Schedule), or (iii) any instrument convertible into or
     exchangeable for any capital stock or other security;

          (e) the Company has not amended or waived any of its rights under, or
     permitted the acceleration of vesting under, (i) any provision of the Stock
     Plan, (ii) any provision of any agreement evidencing any outstanding
     Company Option, or (iii) any restricted stock purchase agreement;

          (f) there has been no amendment to the certificate of incorporation,
     bylaws or other charter or organizational documents of any of the Acquired
     Corporations, and none of the Acquired Corporations has effected or been a
     party to any Acquisition Transaction,


                                       14.
<PAGE>

     recapitalization, reclassification of shares, stock split, reverse stock
     split or similar transaction;

          (g) none of the Acquired Corporations has formed any Subsidiary or
     acquired any equity interest or other interest in any other Entity;

          (h) none of the Acquired Corporations has made any capital expenditure
     which, when added to all other capital expenditures made on behalf of the
     Acquired Corporations since September 30, 2000, exceeds $500,000;

          (i) none of the Acquired Corporations has amended or prematurely
     terminated, or waived any material right or remedy under, any Material
     Contract;

          (j) none of the Acquired Corporations has (i) acquired, leased or
     licensed any right or other asset from any other Person, (ii) sold or
     otherwise disposed of, or leased or licensed, any right or other asset to
     any other Person, or (iii) waived or relinquished any right, except for
     immaterial rights or other immaterial assets acquired, leased, licensed or
     disposed of in the ordinary course of business and consistent with past
     practices;

          (k) none of the Acquired Corporations has written off as
     uncollectible, or established any extraordinary reserve with respect to,
     any account receivable or other indebtedness;

          (l) none of the Acquired Corporations has made any pledge of any of
     its assets or otherwise permitted any of its assets to become subject to
     any Encumbrance, except for pledges of immaterial assets made in the
     ordinary course of business and consistent with past practices;

          (m) none of the Acquired Corporations has (i) lent money to any Person
     (other than pursuant to routine travel advances made to employees in the
     ordinary course of business), or (ii) incurred or guaranteed any
     indebtedness for borrowed money;

          (n) none of the Acquired Corporations has, outside the ordinary course
     of business or inconsistent with past practices, (i) established or adopted
     any Employee Benefit Plan, (ii) paid any bonus or made any profit-sharing
     or similar payment to, or increased the amount of the wages, salary,
     commissions, fringe benefits or other compensation or remuneration payable
     to, any of its directors, officers or employees, or (iii) hired any new
     employee;

          (o) none of the Acquired Corporations has changed any of its methods
     of accounting or accounting practices in any respect;

          (p) none of the Acquired Corporations has made any material Tax
     election;

          (q) none of the Acquired Corporations has commenced or settled any
     Legal Proceeding;


                                       15.
<PAGE>

          (r) none of the Acquired Corporations has entered into any material
     transaction or taken any other material action outside the ordinary course
     of business or inconsistent with past practices; and

          (s) none of the Acquired Corporations has agreed or committed to take
     any of the actions referred to in clauses "(c)" through "(r)" above.

     2.6 TITLE TO ASSETS. The Acquired Corporations own, and have good and
marketable title to, all of the assets purported to be owned by them, including:
(i) all assets reflected on the Unaudited Interim Balance Sheet; (ii) all of the
rights of the Acquired Corporations under the Contracts identified in Part 2.10
of the Company Disclosure Schedule; and (iii) all other assets reflected in the
books and records of the Acquired Corporations as being owned by the Acquired
Corporations. Except as set forth in Part 2.6 of the Company Disclosure
Schedule, all of such assets are owned by the Acquired Corporations free and
clear of any liens or other Encumbrances, except for (x) any lien for current
taxes not yet due and payable, (y) minor liens that have arisen in the ordinary
course of business and that do not (in any case or in the aggregate) materially
detract from the value of the assets subject thereto or materially impair the
operations of any of the Acquired Corporations and (z) Permitted Encumbrances.

     2.7 BANK ACCOUNTS; RECEIVABLES.

          (a) Part 2.7(a) of the Company Disclosure Schedule accurately sets
forth, with respect to each account or credit line maintained by or for the
benefit of each Acquired Corporation at any bank or financial institution:

              (i)   the name and location of the institution at which such
account or credit line is maintained;

              (ii)  the name in which such account or credit line is maintained
and the account number of such account or credit line;

              (iii) a description of such account or credit line and the
purpose for which such account or credit line is used;

              (iv)  the current balance in such account or amount owed under
such credit line;

              (v)   the rate of interest being earned on the funds in such
account or charged under such credit line; and

              (vi)  the names of all individuals authorized to draw on or make
withdrawals from such account or to borrow against such credit line.

          (b) Except as set forth in Part 2.7(b)(i) of the Company Disclosure
Schedule, all existing accounts receivable of the Acquired Corporations
(including those accounts receivable reflected on the Unaudited Interim Balance
Sheet that have not yet been collected and those accounts receivable that have
arisen since September 30, 2000 and have not yet been


                                       16.
<PAGE>

collected) represent valid obligations of customers of the Acquired Corporations
arising from bona fide transactions entered into in the ordinary course of
business. Part 2.7(b)(ii) of the Company Disclosure Schedule accurately
identifies, and provides an accurate and complete breakdown of the revenues
received from, each customer or other Person that accounted for (i) more than
$175,000 of the consolidated gross revenues of the Acquired Corporations in the
fiscal year ended December 31, 1999, or (ii) more than $175,000 of the
consolidated gross revenues of the Acquired Corporations in the nine-month
period ended September 30, 2000 (each, a "Material Customer")(it being
understood that for purposes of clauses "(i)" and "(ii)" of this sentence, a
"Material Customer" of an Acquired Corporation includes any Person to which PPD
provides "Designated Services" or "Designated Products" (as such terms are
defined in the Distributor Agreement dated February 1, 2000 between the Company
and PPD (the "Distributor Agreement")) in accordance with the terms of the
Distributor Agreement). Except as set forth in Part 2.7(c)(iii) of the Company
Disclosure Schedule, the Company has not received any notice or other
communication (in writing or otherwise), and, to the Knowledge of the Company,
has not received any other information, indicating that (a) any Material
Customer is likely to cease dealing with the Company or (b) any Material
Customer is dissatisfied in any material respect with the operation of any
product, system or program currently maintained, sold or licensed by any of the
Acquired Corporations or with any services performed by any of the Acquired
Corporations since January 1, 1999.

     2.8 EQUIPMENT; LEASEHOLD.

          (a) All material items of equipment and other tangible assets owned by
or leased to the Acquired Corporations are, in the reasonable judgment of the
Acquired Corporations, adequate for the uses to which they are being put, are in
good condition and repair (ordinary wear and tear excepted) and are adequate for
the conduct of the business of the Acquired Corporations in the manner in which
such businesses are currently being conducted.

          (b) None of the Acquired Corporations own any real property or any
interest in real property, except for the leaseholds created under the real
property leases identified in Part 2.8 of the Company Disclosure Schedule.

     2.9 PROPRIETARY ASSETS.

          (a) Part 2.9(a)(i) of the Company Disclosure Schedule sets forth, with
respect to each Acquired Corporation Proprietary Asset registered with any
Governmental Body or for which an application has been filed with any
Governmental Body, (i) a brief description of such Acquired Corporation
Proprietary Asset, and (ii) the names of the jurisdictions covered by the
applicable registration or application. Part 2.9(a)(ii) of the Company
Disclosure Schedule identifies and provides a brief description of each
Proprietary Asset (other than trade secrets, know-how or customer list) owned by
any of the Acquired Corporations. Part 2.9(a)(iii) of the Company Disclosure
Schedule identifies and provides a brief description of, and identifies any
ongoing royalty or payment obligations in excess of $10,000 annually with
respect to, each Proprietary Asset that is licensed or otherwise made available
to any of the Acquired Corporations by any Person and is material to the
business of the Acquired Corporations (except for any Proprietary Asset that is
licensed to any Acquired Corporation under any third party


                                       17.
<PAGE>

software license generally available to the public), and identifies the Contract
under which such Proprietary Asset is being licensed or otherwise made available
to such Acquired Corporation. Except as set forth in Part 2.9(a)(iv) of the
Company Disclosure Schedule, each of the Acquired Corporations has good and
valid title to, and exclusive ownership of or exclusive license to use, all of
their respective Proprietary Assets identified or required to be identified in
Parts 2.9(a)(i) and 2.9(a)(ii) of the Company Disclosure Schedule that are
material to the conduct of the business of the Acquired Corporations, free and
clear of all Encumbrances. All of the rights of the Acquired Corporations in all
of such Proprietary Assets are freely transferable, and each of the Acquired
Corporations has a valid right to use, license and otherwise exploit all
Proprietary Assets identified in Part 2.9(a)(iii) of the Company Disclosure
Schedule. Except as set forth in Part 2.9(a)(v) of the Company Disclosure
Schedule, none of the Acquired Corporations has developed jointly with any other
Person any Acquired Corporation Proprietary Asset with respect to which such
other Person has any rights. Except as set forth in Part 2.9(a)(vi) of the
Company Disclosure Schedule, there is no Acquired Corporation Contract pursuant
to which any Person has any right (whether or not currently exercisable) to use,
license or otherwise exploit any Acquired Corporation Proprietary Asset or any
Acquired Corporation Proprietary Asset that may be developed in the future.

          (b) Except as set forth in Part 2.9(b)(i) of the Company Disclosure
Schedule, all such Proprietary Assets have been duly registered with, filed with
or issued by the United States Patent and Trademark Office, the United States
Register of Copyrights, or the corresponding offices of other jurisdictions as
identified in the Company Disclosure Schedule, and have been properly maintained
and renewed in accordance with all applicable provisions of law and
administrative regulations of the United States and each such jurisdiction and,
except as stated in Part 2.9(b)(ii) of the Company Disclosure Schedule, all of
the rights and Proprietary Assets of the Acquired Corporations thereunder are
freely assignable without the consent of any Person.

          (c) Part 2.9(c)(i) of the Company Disclosure Schedule sets forth all
licenses or other Contracts under which the Acquired Corporations are granted
rights in Proprietary Assets. Except as set forth in Part 2.9(c)(ii), all such
licenses or other Contracts are in full force and effect, there is no material
default by any Acquired Corporation or, to the Knowledge of the Company, by any
other party thereto, and, except as set forth in Part 2.9(c)(iii), all of the
rights of the Acquired Corporations thereunder are freely assignable without the
consent of any Person. Except as set forth in Part 2.9(c)(iv), to the Knowledge
of the Company, the licensors under said licenses and other Contracts have and
had all requisite power and authority to grant the rights purported to be
conferred thereby. True and complete copies of all such licenses or other
Contracts, and any amendments thereto, have been provided to Parent.

          (d) Each of the Acquired Corporations has taken reasonable measures
and precautions to protect and maintain the confidentiality, secrecy and value
of all material Acquired Corporation Proprietary Assets (except Acquired
Corporation Proprietary Assets whose value would be unimpaired by disclosure).
Without limiting the generality of the foregoing, except as set forth in Part
2.9(d) of the Company Disclosure Schedule, (i) each current or former employee
of any Acquired Corporation who is or was involved in, or who has contributed
to, the creation or development of any material Acquired Corporation Proprietary


                                       18.
<PAGE>

Asset has executed and delivered to such Acquired Corporation an agreement
(containing no exceptions to or exclusions from the scope of its coverage) that
is substantially identical to the form of the Company's Employment, Confidential
Information and Invention Assignment Agreement previously delivered by the
Company to Parent, and (ii) each current and former consultant and independent
contractor to any Acquired Corporation who is or was involved in, or who has
contributed to, the creation or development of any material Acquired Corporation
Proprietary Asset has executed and delivered to the Company an agreement
(containing no material exceptions to or exclusions from the scope of its
coverage) that is substantially identical to the form of the Company's
Employment, Confidential Information and Invention Assignment Agreement
previously delivered to Parent. No current or former employee, officer,
director, stockholder, consultant or independent contractor has any right, claim
or interest in or with respect to any material Acquired Corporation Proprietary
Asset.

          (e) To the Knowledge of the Company: (i) all patents, trademarks,
service marks and copyrights held by any of the Acquired Corporations are valid,
enforceable and subsisting; (ii) none of the Acquired Corporation Proprietary
Assets and no Proprietary Asset that is currently being developed by any of the
Acquired Corporations (either by itself or with any other Person)
misappropriates any Proprietary Asset owned or used by any other Person, and the
use of Acquired Corporation Proprietary Assets in their intended or contemplated
manner does not require a license under or other rights to use any Proprietary
Asset owned by any other Person; (iii) none of the products, formula,
compositions of matter, inventions, designs, technology, proprietary rights or
other intellectual property rights or intangible assets that is or has been
designed, created, developed, assembled, manufactured or sold by any of the
Acquired Corporations is infringing, misappropriating or making any unlawful or
unauthorized use of any Proprietary Asset owned or used by any other Person, and
none of such products has at any time infringed, misappropriated or made any
unlawful or unauthorized use of any Proprietary Asset owned or used by any other
Person; (iv) except as set forth in Part 2.9(e) of the Company Disclosure
Schedule, none of the Acquired Corporations has received any notice or other
communication (in writing or otherwise) of any actual, alleged, possible or
potential infringement, misappropriation or unlawful or unauthorized use of, any
Proprietary Asset owned or used by any other Person; and (v) no other Person is
infringing, misappropriating or making any unlawful or unauthorized use of any
material Acquired Corporation Proprietary Asset.

          (f) To the Knowledge of the Company, the Acquired Corporation
Proprietary Assets constitute all the Proprietary Assets necessary to enable the
Acquired Corporations to conduct their business in the manner in which such
business is presently being conducted. Except as set forth in Part 2.9(f) of the
Company Disclosure Schedule, none of the Acquired Corporations has (i) licensed
any of the Acquired Corporation Proprietary Assets to any Person on an exclusive
basis, or (ii) entered into any covenant not to compete or Contract limiting or
purporting to limit the ability of any Acquired Corporation to exploit fully any
material Acquired Corporation Proprietary Assets or to transact business in any
market or geographical area or with any Person.

          (g) Notwithstanding the generality of anything stated in this Section
2.9, the Company owns (and immediately after the Effective Time, the Surviving
Corporation shall own), subject to Third-Party Rights, the entire right, title
and interest in and to the DNA Sample

                                       19.
<PAGE>

Library and any information, including but not limited to, genotypic and
phenotypic information, derived or developed by the Company from the DNA Sample
Library. All right, title and interest owned by the Company in and to the DNA
Sample Library and information derived or developed by the Company from the DNA
Sample Library is freely transferable, subject only to the Third Party Rights.
For purposes of this Agreement: (1) the "DNA Sample Library" means the library
of DNA specimens identified in Part 2.9(g) of the Company Disclosure Schedule;
and (2) "Third-Party Rights" means those rights retained by Persons other than
the Company and/or the Major Stockholders pursuant to those Contracts identified
in Part 2.9(g) of the Company Disclosure Schedule.

     2.10 CONTRACTS.

          (a) Part 2.10 of the Company Disclosure Schedule identifies each
Acquired Corporation Contract that constitutes a "Material Contract" as of the
date of this Agreement. For purposes of this Agreement, each of the following
Contracts (to the extent that any of the Acquired Corporations has (or may have)
any liability or obligation thereunder or with respect thereto after the date of
this Agreement) shall be deemed to constitute a "Material Contract":

               (i)   each Contract relating to the employment of, or the
performance of services by, any employee or consultant (other than any offer
letter provided to any employee of any of the Acquired Corporations which
provides for "at will" employment);

               (ii)  each Contract pursuant to which any of the Acquired
Corporations is or may become obligated to make any severance, termination or
similar payment to any current or former employee or director; and any Contract
pursuant to which any of the Acquired Corporations is or may become obligated to
make any bonus or similar payment (other than payments in respect of salary or
commissions) in excess of $15,000 to any current or former employee or director;

               (iii) each Contract with a face value of $25,000 (A) with any
customer of any of the Acquired Corporations except for standard purchase
orders; or (B) with respect to the distribution or marketing of any product of
any of the Acquired Corporations;

               (iv)  each Contract relating to the acquisition, transfer,
development, sharing or license of any Acquired Corporation Proprietary Asset
(except for any Contract pursuant to which any Proprietary Asset is licensed by
any of the Acquired Corporations to any Person (other than a Major Stockholder)
on a non-exclusive basis);

               (v)   each Contract which provides for indemnification of any
officer, director, employee or agent;

               (vi)  each Contract creating or relating to any partnership or
joint venture or any sharing of revenues, profits, losses, costs or liabilities;

               (vii) each Contract relating to the purchase or sale of any
product or other asset by or to, or the performance of any services by or for,
any Related Party;

                                       20.
<PAGE>

               (viii) each Contract imposing any restriction on the right or
ability of any Acquired Corporation (A) to compete with any other Person, (B) to
acquire any material product or other asset or any services from any other
Person, (C) to solicit, hire or retain any Person as an employee, consultant or
independent contractor, (D) to develop, sell, supply, distribute, offer, support
or service any product or any technology or other asset to or for any other
Person, (E) to perform services for any other Person or (F) to transact business
or deal in any other manner with any other Person;

               (ix)  each Contract creating or involving any agency
relationship, distribution arrangement or franchise relationship;

               (x)   each Contract relating to the creation of any Encumbrance
(except Permitted Encumbrances) with respect to any asset of any of the Acquired
Corporations;

               (xi)  each Contract (A) relating to the acquisition, issuance,
voting, registration, sale or transfer of any securities, other than pursuant to
the Company Options, (B) providing any Person with any preemptive right, right
of participation, right of maintenance or any similar right with respect to any
securities or (C) providing any of the Acquired Corporations with any right of
first refusal with respect to, or right to purchase or otherwise acquire, any
securities;

               (xii) each Contract incorporating or relating to any guaranty or
any indemnity or similar obligation, except for Contracts entered into in the
ordinary course of business;

               (xiii) each Contract relating to any currency hedging;

               (xiv) each Contract imposing any confidentiality obligation on
any of the Acquired Corporations other than nondisclosure agreements entered
into in the ordinary course of business;

               (xv)  each Contract to which any Governmental Body is a party;
and any other Contract directly or indirectly benefiting any Governmental Body
(including any subcontract or other Contract between any Acquired Corporation
and any contractor or subcontractor to any Governmental Body), except for
Contracts entered into in the ordinary course of business for the license,
maintenance or service of products;

               (xvi) each Contract with obligations in excess of $50,000 that
has a term of more than 60 days and that may not be terminated by an Acquired
Corporation (without penalty) within 60 days after the delivery of a termination
notice by such Acquired Corporation;

               (xvii) each Contract that contemplates or involves the payment or
delivery of cash or other consideration in an amount or having a value in excess
of $50,000 in the aggregate, or contemplates or involves the performance of
services having a value in excess of $50,000 in the aggregate;

                                       21.
<PAGE>

               (xviii) each Contract requiring that any of the Acquired
Corporations give any notice or provide any information to any Person prior to
considering or accepting any Acquisition Proposal or similar proposal, or prior
to entering into any discussions, agreement, arrangement or understanding
relating to any Acquisition Transaction or similar transaction;

               (xix)   each Contract that (A) contemplates or involves the
payment or delivery of cash or other consideration by any of the Acquired
Corporations in an amount or having a value in excess of $100,000 in the
aggregate, (B) contemplates or involves the payment or delivery of cash or other
consideration to any of the Acquired Corporations in an amount or having a value
in excess of $100,000 in the aggregate or (C) contemplates or involves the
performance of services by any of the Acquired Corporations having a value in
excess of $100,000 in the aggregate;

               (xx)    each Contract that could reasonably be expected to have a
material effect on (A) the business, condition, capitalization, assets,
liabilities, operations, financial performance of any of the Acquired
Corporations or (B) the ability of the Company to perform any of its obligations
under, or to consummate any of the transactions contemplated by, this Agreement;
and

               (xxi)   each Contract (not otherwise identified in clauses "(i)"
through "(xx)" of this sentence) with a Major Stockholder and/or one or more of
its Subsidiaries.

          (b) The Company has delivered to Parent and to Cooley Godward LLP an
accurate and complete copy of each Material Contract.

          (c) Each Acquired Corporation Contract is valid and in full force and
effect, and is enforceable in accordance with its terms, subject to (i) laws of
general application relating to bankruptcy, insolvency and the relief of
debtors, and (ii) applicable Legal Requirements governing specific performance,
injunctive relief and other equitable remedies, except where the failure to be
valid and binding and in full force and effect would not individually or in the
aggregate have a Material Adverse Effect on the Acquired Corporations.

          (d) Except as set forth in Part 2.10(d) of the Company Disclosure
Schedule: (i) none of the Acquired Corporations has violated or breached, or
committed any default under, any Acquired Corporation Contract, except for
violations, breaches and defaults that have not had and would not reasonably be
expected to have a Material Adverse Effect on the Acquired Corporations; and, to
the Knowledge of the Company, no other Person has violated or breached, or
committed any default under, any Acquired Corporation Contract, except for
violations, breaches or defaults that have not had and would not reasonably be
expected to have a Material Adverse Effect on the Acquired Corporations; (ii) to
the Knowledge of the Company, no event has occurred, and no circumstance or
condition exists, that (with or without notice or lapse of time) will, or would
reasonably be expected to, (A) result in a violation or breach of any of the
provisions of any Acquired Corporation Contract, (B) give any Person the right
to declare a default or exercise any remedy under any Acquired Corporation
Contract, (C) give any Person the right to receive or require a rebate,
chargeback or penalty under any Acquired Corporation Contract, (D) give any
Person the right to accelerate the maturity or performance of any

                                       22.
<PAGE>

Acquired Corporation Contract, or (E) give any Person the right to cancel,
terminate or modify any Acquired Corporation Contract, except in each such case
for defaults, acceleration rights, termination rights and other rights that have
not had and would not reasonably be expected to have a Material Adverse Effect
on the Acquired Corporations; and (iii) since January 1, 1999, none of the
Acquired Corporations has received any notice or other communication regarding
any actual or possible violation or breach of, or default under, any Acquired
Corporation Contract, except in each such case for defaults, acceleration
rights, termination rights and other rights that have not had and would not
reasonably be expected to have a Material Adverse Effect on the Acquired
Corporations.

     2.11 LIABILITIES. None of the Acquired Corporations has accrued,
contingent or other liabilities of any nature, either matured or unmatured
(whether or not required to be reflected in financial statements in accordance
with generally accepted accounting principles, and whether due or to become
due), except for: (a) liabilities identified as such in the "liabilities" column
of the Unaudited Interim Balance Sheet; (b) accounts payable or accrued salaries
that have been incurred by the Acquired Corporations since September 30, 2000 in
the ordinary course of business and consistent with past practices; (c)
liabilities under the Acquired Corporation Contracts identified in Part 2.10 of
the Company Disclosure Schedule, to the extent the nature and magnitude of such
liabilities can be specifically ascertained by reference to the text of such
Acquired Corporation Contracts; and (d) the liabilities identified in Part 2.11
of the Company Disclosure Schedule.

     2.12 COMPLIANCE WITH LEGAL REQUIREMENTS. Each of the Acquired
Corporations is, and has at all times since January 1, 1999 been, in compliance
with all applicable Legal Requirements, except where the failure to comply with
such Legal Requirements has not had and will not have a Material Adverse Effect
on the Acquired Corporations. Except as set forth in Part 2.12 of the Company
Disclosure Schedule, since January 1, 1999, none of the Acquired Corporations
has received any notice or other communication from any Governmental Body
regarding any actual or possible violation (or of any pending or threatened
investigation, inspection, audit or other proceeding by any Governmental Body
involving allegations of any violation) of, or failure to comply with, any Legal
Requirement. To the Knowledge of the Company, no investigation, inspection,
audit or other proceeding by Governmental Body involving allegations of any
violation of any Legal Requirement is contemplated by any such Governmental
Body.

     2.13 GOVERNMENTAL AUTHORIZATIONS AND FACILITY CERTIFICATIONS.

          (a) Part 2.13(a) of the Company Disclosure Schedule identifies each
material Governmental Authorization held by the Acquired Corporations (and
contains a summary description of each such Governmental Authorization and,
where applicable, specifies the date issued, granted or applied for, the
expiration date and the current status thereof), and the Company has delivered
to Parent accurate and complete copies of all Governmental Authorizations
identified in Part 2.13(a) of the Company Disclosure Schedule.

          (b) The Governmental Authorizations identified in Part 2.13(a) of the
Company Disclosure Schedule are valid and in full force and effect (and, to the
Knowledge of


                                       23.
<PAGE>

the Company, no revocation, withdrawal, suspension, cancellation, termination or
modification thereof has been threatened), and collectively constitute all
Governmental Authorizations necessary to enable the Acquired Corporations to
conduct their respective businesses in the manner in which such businesses are
currently being conducted, except where the failure to hold such Governmental
Authorizations has not had, and based on applicable Legal Requirements as in
effect on the date hereof would not reasonably be expected to have, a Material
Adverse Effect on the Acquired Corporations. Each of the Acquired Corporations
is, and at all times since January 1, 1999 has been, in substantial compliance
with the terms and requirements of such Governmental Authorizations, except
where the failure to be in compliance with the terms and requirements of such
Governmental Authorizations has not had, and based on applicable Legal
Requirements as in effect on the date hereof would not reasonably be expected to
have, a Material Adverse Effect on any of the Acquired Corporations. Since
January 1, 1999, none of the Acquired Corporations has received any written
notice from any Governmental Body regarding (a) any actual or possible violation
of or failure to comply with any term or requirement of any material
Governmental Authorization, or (b) any actual or possible revocation,
withdrawal, suspension, cancellation, termination or modification of any
material Governmental Authorization.

          (c) The certifications identified in Part 2.13(c) of the Company
Disclosure Schedule are valid and in full force and effect (and, to the
Knowledge of the Company, no revocation, withdrawal, suspension, cancellation,
termination, modification or limitation thereof has been threatened). Each of
the Acquired Corporations is, and at all times since January 1, 1999 has been,
in substantial compliance with the terms and requirements of such
certifications, except where the failure to be in compliance with the terms and
requirements of such certifications has not had, and based on the terms of such
certifications would not reasonably be expected to have, a Material Adverse
Effect on any of the Acquired Corporations. Since January 1, 1999, none of the
Acquired Corporations has received any written notice from the Person that
issued each such certification regarding (a) any actual or possible violation of
or failure to comply with any term or requirement of such certification, or (b)
any actual or possible revocation, withdrawal, suspension, cancellation,
termination, modification or limitation of such certification.

     2.14 TAX MATTERS.

          (a) Each of the Tax Returns relating to income taxes required to be
filed by or on behalf of the respective Acquired Corporations with any
Governmental Body with respect to any taxable period ending on or before the
Closing has been or will be filed on or before the applicable due date
(including any extensions of such due date). Each of the Tax Returns required to
be filed by or on behalf of the respective Acquired Corporations with any
Governmental Body with respect to any taxable period ending on or before the
Closing (the "Acquired Corporation Returns") has been, or will be when filed,
accurately and completely prepared in all material respects in compliance with
all applicable Legal Requirements. All amounts shown on the Acquired Corporation
Returns to be due on or before the Closing have been or will be paid on or
before the Closing. The Company has delivered to Parent accurate and complete
copies of all Acquired Corporation Returns filed since December 31, 1999 which
have been requested by Parent.

                                       24.
<PAGE>

          (b) The Financial Statements of the Acquired Corporations fully accrue
all actual and contingent liabilities for Taxes with respect to all periods
through the dates thereof in accordance with generally accepted accounting
principles. The Acquired Corporations will establish, in the ordinary course of
business and consistent with its past practices, reserves adequate for the
payment of all Taxes for the period from September 30, 2000 through the Closing,
and the Company will disclose the dollar amount of such reserves to Parent on or
prior to the Closing.

          (c) No Acquired Corporation Return has ever been examined or audited
by any Governmental Body. Except as set forth in Part 2.14 of the Company
Disclosure Schedule, there have been no examinations or audits of any Acquired
Corporation Returns. The Company has delivered to Parent accurate and complete
copies of all audit reports and similar documents (to which the Company has
access) relating to the Acquired Corporation Returns. Except as set forth in
Part 2.14 of the Company Disclosure Schedule, no extension or waiver of the
limitation period applicable to any of the Acquired Corporation Returns has been
granted (by the Company or any other Person), and no such extension or waiver
has been requested from any Acquired Corporation.

          (d) Except as set forth in Part 2.14 of the Company Disclosure
Schedule, no claim or Proceeding is, to the Knowledge of the Company, pending or
has been threatened against or with respect to any Acquired Corporation in
respect of any Tax. There are no unsatisfied liabilities for Taxes (including
liabilities for interest, additions to tax and penalties thereon and related
expenses) with respect to any notice of deficiency or similar document received
by any of the Acquired Corporations with respect to any Tax (other than
liabilities for Taxes asserted under any such notice of deficiency or similar
document which are being contested in good faith by the Acquired Corporations
and with respect to which adequate reserves for payment have been established).
There are no liens for Taxes upon any of the assets of any of the Acquired
Corporations except liens for current Taxes not yet due and payable. None of the
Acquired Corporations has entered into or become bound by any agreement or
consent pursuant to Section 341(f) of the Code. None of the Acquired
Corporations has been, and none of the Acquired Corporations will be, required
to include any adjustment in taxable income for any tax period (or portion
thereof) pursuant to Section 481 or 263A of the Code or any comparable provision
under state or foreign Tax laws as a result of transactions or events occurring,
or accounting methods employed, prior to the Closing.

          (e) There is no agreement, plan, arrangement or other Contract
covering any employee or independent contractor or former employee or
independent contractor of any of the Acquired Corporations that, considered
individually or considered collectively with any other such Contracts, will, or
could reasonably be expected to, give rise directly or indirectly to the payment
of any amount that would not be deductible pursuant to Section 280G or Section
162 of the Code. None of the Acquired Corporations are, or have ever been, a
party to or bound by any tax indemnity agreement, tax-sharing agreement, tax
allocation agreement or similar Contract.

     2.15 EMPLOYEE AND LABOR MATTERS; BENEFIT PLANS.

                                       25.
<PAGE>

          (a) Part 2.15(a) of the Company Disclosure Schedule identifies each
bonus, deferred compensation, incentive compensation, stock purchase, stock
option, severance pay, termination pay, hospitalization, medical, life or other
insurance, supplemental unemployment benefits, profit-sharing, pension or
retirement plan, program or agreement (collectively, the "Plans") sponsored,
maintained, contributed to or required to be contributed to by any of the
Acquired Corporations for the benefit of any employee of any of the Acquired
Corporations ("Employee"), except for (1) Plans which would not require any of
the Acquired Corporations to make payments or provide benefits having a value in
excess of $25,000 in the aggregate and (2) except for the Company's 2000 Merit
Compensation Plan and 2000 Incentive Compensation Plan.

          (b) Except as set forth in Part 2.15(b) of the Company Disclosure
Schedule, none of the Acquired Corporations maintains, sponsors or contributes
to, and, to the Knowledge of the Company, none of the Acquired Corporations has
at any time in the past maintained, sponsored or contributed to, any employee
pension benefit plan (as defined in Section 3(2) of the Employee Retirement
Income Security Act of 1974, as amended ("ERISA"), whether or not excluded from
coverage under specific Titles or Merger Subtitles of ERISA) for the benefit of
Employees or former Employees (a "Pension Plan").

          (c) Each of the Acquired Corporations maintains, sponsors or
contributes only to those employee welfare benefit plans (as defined in Section
3(1) of ERISA, whether or not excluded from coverage under specific Titles or
Merger Subtitles of ERISA) for the benefit of Employees or former Employees
which are described in Part 2.15(c) of the Company Disclosure Schedule (the
"Welfare Plans"), none of which is a multiemployer plan (within the meaning of
Section 3(37) of ERISA).

          (d) With respect to each Plan, the Company has delivered or made
available to Parent:

               (i)   an accurate and complete copy of such Plan (including all
amendments thereto);

               (ii)  an accurate and complete copy of the annual report, if
required under ERISA, with respect to such Plan for the last two years;

               (iii) an accurate and complete copy of the most recent summary
plan description, together with each Summary of Material Modifications, if
required under ERISA, with respect to such Plan, and all material employee
communications relating to such Plan;

               (iv)  if such Plan is funded through a trust or any third party
funding vehicle, an accurate and complete copy of the trust or other funding
agreement (including all amendments thereto) and accurate and complete copies
the most recent financial statements thereof;

               (v)   accurate and complete copies of all Contracts relating to
such Plan, including service provider agreements, insurance contracts, minimum
premium contracts, stop-


                                       26.
<PAGE>

loss agreements, investment management agreements, subscription and
participation agreements and recordkeeping agreements; and

               (vi) an accurate and complete copy of the most recent
determination letter received from the Internal Revenue Service with respect to
such Plan (if such Plan is intended to be qualified under Section 401(a) of the
Code).

          (e) None of the Acquired Corporations are required to be, and, to the
Knowledge of the Company, has ever been required to be, treated as a single
employer with any other Person under Section 4001(b)(1) of ERISA or Section
414(b), (c), (m) or (o) of the Code. None of the Acquired Corporations has ever
been a member of an "affiliated service group" within the meaning of Section
414(m) of the Code. To the Knowledge of the Company, none of the Acquired
Corporations has ever made a complete or partial withdrawal from a multiemployer
plan, as such term is defined in Section 3(37) of ERISA, resulting in
"withdrawal liability," as such term is defined in Section 4201 of ERISA
(without regard to subsequent reduction or waiver of such liability under either
Section 4207 or 4208 of ERISA).

          (f) None of the Acquired Corporations has any plan or commitment to
create any additional Welfare Plan or any Pension Plan, or to modify or change
any existing Welfare Plan or Pension Plan (other than to comply with applicable
law) in a manner that would affect any Employee.

          (g) Except as set forth in Part 2.15(g) of the Company Disclosure
Schedule, no Welfare Plan provides death, medical or health benefits (whether or
not insured) with respect to any current or former Employee after any such
Employee's termination of service (other than (i) benefit coverage mandated by
applicable law, including coverage provided pursuant to Section 4980B of the
Code, (ii) deferred compensation benefits accrued as liabilities on the
Unaudited Interim Balance Sheet, and (iii) benefits the full cost of which are
borne by current or former Employees (or the Employees' beneficiaries)).

          (h) With respect to each of the Welfare Plans constituting a group
health plan within the meaning of Section 4980B(g)(2) of the Code, the
provisions of Section 4980B of the Code ("COBRA") have been complied with in all
material respects.

          (i) Each of the Plans has been operated and administered in all
material respects in accordance with applicable Legal Requirements, including
but not limited to ERISA and the Code.

          (j) Each of the Plans intended to be qualified under Section 401(a) of
the Code has received a favorable determination from the Internal Revenue
Service, and the Company is not aware of any reason why any such determination
letter should be revoked.

          (k) Except as set forth in Part 2.15(k) of the Company Disclosure
Schedule, neither the execution, delivery or performance of this Agreement, nor
the consummation of the Merger or any of the other transactions contemplated by
this Agreement, will result in any payment (including any bonus, golden
parachute or severance payment) to any current or former Employee or director of
any of the Acquired Corporations (whether or not under any Plan), or

                                       27.
<PAGE>

materially increase the benefits payable under any Plan, or result in any
acceleration of the time of payment or vesting of any such benefits.

          (l) The Company has provided Parent a list of all salaried employees
of each of the Acquired Corporations as of the date of this Agreement, and such
list correctly reflects, in all material respects, their salaries, any other
compensation payable to them (including compensation payable pursuant to bonus,
deferred compensation or commission arrangements), their dates of employment and
their positions. None of the Acquired Corporations is a party to any collective
bargaining contract or other Contract with a labor union representing any of its
Employees. All of the employees of the Acquired Corporations are "at will"
employees.

          (m) Part 2.15(m) of the Company Disclosure Schedule identifies each
Employee who is not fully available to perform work because of disability or
other leave and sets forth the basis of such leave and the anticipated date of
return to full service.

          (n) Each of the Acquired Corporations is in compliance in all material
respects with all applicable Legal Requirements and Contracts relating to
employment, employment practices, wages, bonuses and terms and conditions of
employment, including employee compensation matters.

          (o) Except as set forth in Part 2.15(o) of the Company Disclosure
Schedule, each of the Acquired Corporations has good labor relations and the
Company has no Knowledge that (i) the consummation of the Merger or any of the
other transactions contemplated by this Agreement will have a material adverse
effect on the labor relations of any of the Acquired Corporations, or (ii) any
officer or head of facility of any of the Acquired Corporations intends to
terminate his or her employment with such Acquired Corporation.

     2.16 ENVIRONMENTAL MATTERS. Each of the Acquired Corporations is in
compliance in all material respects with all applicable Environmental Laws,
which compliance includes the possession by each of the Acquired Corporations of
all permits and other Governmental Authorizations required under applicable
Environmental Laws, and compliance with the terms and conditions thereof. None
of the Acquired Corporations has received any notice or other communication (in
writing or otherwise), whether from a Governmental Body, citizens group,
employee or otherwise, that alleges that any of the Acquired Corporations are
not in compliance with any Environmental Law, and, to the Knowledge of the
Company, there are no circumstances that may prevent or interfere with the
compliance of the Acquired Corporations with any Environmental Law in the
future. To the Knowledge of the Company, no current or prior owner of any
property leased or controlled by any of the Acquired Corporations has received
any notice or other communication (in writing or otherwise), whether from a
Government Body, citizens group, employee or otherwise, that alleges that such
current or prior owner or any of the Acquired Corporations is not in compliance
with any Environmental Law. All Governmental Authorizations currently held by
the Acquired Corporations pursuant to Environmental Laws are identified in Part
2.16 of the Company Disclosure Schedule. (For purposes of this Section 2.16: (i)
"Environmental Law" means any federal, state, local or foreign Legal Requirement
relating to pollution or protection of human health or the environment
(including ambient air, surface water, ground water, land surface or subsurface
strata), including

                                       28.
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any law or regulation relating to emissions, discharges, releases or threatened
releases of Materials of Environmental Concern, or otherwise relating to the
manufacture, processing, distribution, use, treatment, storage, disposal,
transport or handling of Materials of Environmental Concern; and (ii) "Materials
of Environmental Concern" include chemicals, pollutants, contaminants, wastes,
toxic substances, petroleum and petroleum products and any other substance that
is now or hereafter regulated by any Environmental Law or that is otherwise a
danger to health, reproduction or the environment.)

     2.17 INSURANCE. Part 2.17 of the Company Disclosure Schedule
identifies all insurance policies maintained by, at the expense of or for the
benefit of each of the Acquired Corporations and identifies any material claims
made thereunder since January 1, 1999, and the Company has delivered to Parent
accurate and complete copies of the insurance policies identified on Part 2.17
of the Company Disclosure Schedule. Each of the insurance policies identified in
Part 2.17 of the Company Disclosure Schedule is in full force and effect. Since
December 31, 1999, none of the Acquired Corporations has received any notice or
other communication regarding any actual or possible (a) cancellation or
invalidation of any insurance policy, (b) refusal of any coverage or rejection
of any claim under any insurance policy, or (c) material adjustment in the
amount of the premiums payable with respect to any insurance policy.

     2.18 RELATED PARTY TRANSACTIONS. Except as set forth in Part 2.18 of
the Company Disclosure Schedule: (a) no Related Party has, and no Related Party
has at any time since December 31, 1999 had, any direct or indirect interest in
any material asset used in or otherwise relating to the business of any of the
Acquired Corporations; (b) no Related Party is, or has at any time since
December 31, 1999 been, indebted to any of the Acquired Corporations; (c) since
December 31, 1999, no Related Party has entered into, or has had any direct or
indirect financial interest in, any material Contract, transaction or business
dealing involving any of the Acquired Corporations; (d) no Related Party is
competing, or has at any time since December 31, 1999 competed, directly or
indirectly, with any of the Acquired Corporations; and (e) no Related Party has
any claim or right against any of the Acquired Corporations (other than rights
under Company Options and rights to receive compensation for services performed
as an employee of the Company). (For purposes of this Section 2.18, each of the
following shall be deemed to be a "Related Party": (i) each individual who is,
or who has at any time since December 31, 1999 been, an officer of any of the
Acquired Corporations; (ii) each member of the immediate family of each of the
individuals referred to in clause "(i)" above; and (iii) any trust or other
Entity (other than the Acquired Corporations) in which any one of the
individuals referred to in clauses "(i)" or "(ii)" above holds (or in which more
than one of such individuals collectively hold), beneficially or otherwise, a
material voting, proprietary or equity interest.)

     2.19 LEGAL PROCEEDINGS; ORDERS.

          (a) Except as set forth in Part 2.19 of the Company Disclosure
Schedule, there is no pending Legal Proceeding, and (to the Knowledge of the
Company) no Person has threatened to commence any Legal Proceeding: (i) that
involves any of the Acquired Corporations or any of the assets owned or used by
any of the Acquired Corporations or any Person whose liability the Acquired
Corporations has or may have retained or assumed, either contractually or by
operation of law; or (ii) that challenges, or that may have the effect of


                                       29.
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preventing, delaying, making illegal or otherwise interfering with, the Merger
or any of the other transactions contemplated by this Agreement. To the
Knowledge of the Company, except as set forth in Part 2.19 of the Company
Disclosure Schedule, no event has occurred, and no claim, dispute or other
condition or circumstance exists, that will, or that could reasonably be
expected to, give rise to or serve as a basis for the commencement of any such
Legal Proceeding.

          (b) Except as set forth in Part 2.19 of the Company Disclosure
Schedule, no Legal Proceeding has ever been commenced by or has ever been
pending against any of the Acquired Corporations.

          (c) There is no order, writ, injunction, judgment or decree to which
any of the Acquired Corporations, or any of the assets owned or used by any of
the Acquired Corporations, are subject. To the Knowledge of the Company, no
officer or other employee of any of the Acquired Corporations is subject to any
order, writ, injunction, judgment or decree that prohibits such officer or other
employee from engaging in or continuing any conduct, activity or practice
relating to the business of any of the Acquired Corporations.

     2.20 AUTHORITY; BINDING NATURE OF AGREEMENT. The Company has the
absolute and unrestricted right, power and authority to enter into and to
perform its obligations under this Agreement; and the execution, delivery and
performance by the Company of this Agreement have been duly authorized by all
necessary action on the part of the Company and its board of directors. This
Agreement constitutes the legal, valid and binding obligation of the Company,
enforceable against the Company in accordance with its terms, subject to (i)
laws of general application relating to bankruptcy, insolvency and the relief of
debtors, and (ii) rules of law governing specific performance, injunctive relief
and other equitable remedies.

     2.21 NON-CONTRAVENTION; CONSENTS. Except as set forth in Part 2.21 of
the Company Disclosure Schedule, neither (1) the execution, delivery or
performance of this Agreement or any of the other agreements referred to in this
Agreement, nor (2) the consummation of the Merger or any of the other
transactions contemplated by this Agreement, will directly or indirectly (with
or without notice or lapse of time):

          (a) contravene, conflict with or result in a violation of (i) any of
     the provisions of the certificate of incorporation, bylaws or other charter
     or similar organizational documents of any of the Acquired Corporations, or
     (ii) any resolution adopted by the stockholders, the board of directors or
     any committee of the board of directors of any of the Acquired
     Corporations;

          (b) contravene, conflict with or result in a violation of, or give any
     Governmental Body or other Person the right to challenge any of the
     transactions contemplated by this Agreement or to exercise any remedy or
     obtain any relief under, any Legal Requirement or any order, writ,
     injunction, judgment or decree to which any of the Acquired Corporations,
     or any of the assets owned or used by any of the Acquired Corporations, is
     subject;

                                       30.
<PAGE>

          (c) contravene, conflict with or result in a violation of any of the
     terms or requirements of, or give any Governmental Body the right to
     revoke, withdraw, suspend, cancel, terminate or modify, any Governmental
     Authorization that is held by any of the Acquired Corporations or that
     otherwise relates to the business or to any of the assets owned or used by
     any of the Acquired Corporations;

          (d) contravene, conflict with or result in a violation or breach of,
     or result in a default under, any provision of any Acquired Corporation
     Contract that is or would constitute a Material Contract, or give any
     Person the right to (i) declare a default or exercise any remedy under any
     such Material Contract, (ii) accelerate the maturity or performance of any
     such Material Contract, or (iii) cancel, terminate or modify any such
     Material Contract; or

          (e) result in the imposition or creation of any lien or other
     Encumbrance upon or with respect to any asset owned or used by any of the
     Acquired Corporations (except for Permitted Encumbrances).

Except as set forth in Part 2.21 of the Company Disclosure Schedule, none of the
Acquired Corporations was, is or will be required to make any filing with or
give any notice to, or to obtain any Consent from, any Person in connection with
(x) the execution, delivery or performance of this Agreement or any of the other
agreements referred to in this Agreement, or (y) the consummation of the Merger
or any of the other transactions contemplated by this Agreement.

     2.22 INAPPLICABILITY OF SECTION 2115 OF CALIFORNIA CORPORATIONS CODE. The
Company is not subject to Section 2115 of the California Corporations Code.

     2.23 VOTE REQUIRED. The affirmative vote of holders of at least (i) a
majority of the outstanding shares of the Company Common Stock and the Company
Series A Preferred Stock, voting together as a single class, and (ii) a majority
of the outstanding shares of the Company Series A Preferred Stock, voting as a
separate class (the "Required Vote") is the vote necessary to adopt and approve
this Agreement, the Merger and the other transactions contemplated by this
Agreement.

     2.24 BROKERS OR FINDERS. Except for the fees, costs and expenses payable to
the Company Financial Advisor and incurred in connection with the transactions
contemplated by this Agreement, the Acquired Corporations have not incurred, and
will not incur, directly or indirectly, any liability for brokerage or finders'
fees or agents' commissions or any similar charges in connection with the
transactions contemplated by this Agreement.

     2.25 FULL DISCLOSURE.

          (a) No representation or warranty made by the Company in this
Agreement (including the Company Disclosure Schedule) (i) contains any
information that is false or misleading with respect to any material fact, or
(ii) omits to state any material fact necessary in order to make such
representations and warranties (in the light of the circumstances under which
such representations, warranties were made) false or misleading.

                                       31.
<PAGE>

          (b) The information supplied by the Company for inclusion in the
Information Statement (as defined in Section 5.2) will not, as of the date of
the Information Statement or as of the date of the Company Stockholders' Meeting
(as defined in Section 5.3), (i) contain any statement that is inaccurate or
misleading with respect to any material fact, or (ii) omit to state any material
fact necessary in order to make such information (in the light of the
circumstances under which it is provided) not false or misleading.

SECTION 3.  REPRESENTATIONS AND WARRANTIES OF PARENT AND MERGER SUB

          Except as otherwise set forth in the Parent Disclosure Schedule,
Parent and Merger Sub jointly and severally represent and warrant to the Company
as follows:

     3.1 ORGANIZATION AND STANDING; ARTICLES AND BYLAWS. Each of Parent and
Merger Sub is a corporation duly organized and validly existing under, and by
virtue of, the laws of the State of Delaware and is in good standing under such
laws. Each of Parent and Merger Sub has all requisite corporate power to own and
operate its respective properties and assets, and to carry on its respective
business as presently conducted and as proposed to be conducted. Each of Parent
and Merger Sub is qualified to do business as a foreign corporation in any
jurisdiction in which failure to qualify would have a material adverse effect on
Parent's business. Parent has furnished the Company true and complete copies of
its restated certificate of incorporation (the "Restated Certificate") and
bylaws in effect as of the date hereof. Other than Merger Sub, Parent has no
Subsidiaries and does not otherwise own or control any other Entity. Parent has
no equity interest in any Entity other than Merger Sub.

     3.2 CAPITALIZATION. As of the date of this Agreement, the authorized
capital stock of Parent consists of 40,000,000 shares of Parent Common Stock,
4,721,364 shares of which are issued and outstanding, and 22,000,000 shares of
Preferred Stock, 8,283,000 shares of which are designated as Series A Preferred
Stock, all of which are issued and outstanding, 7,099,006 shares of which are
designated Series B Preferred Stock, all of which are issued and outstanding,
5,500,000 of which are designated as Series C Preferred Stock, 1,644,076 of
which are issued and outstanding. All such issued and outstanding shares have
been duly authorized and validly issued, and are fully paid and non-assessable
and have been issued in compliance with all federal and applicable state
securities laws. Parent has reserved 8,283,000 shares of Parent Common Stock for
issuance upon conversion of its Series A Preferred, 7,099,006 shares of Parent
Common Stock for issuance upon conversion of its Series B Preferred, 5,500,000
shares of Parent Common Stock for issuance upon conversion of its Series C
Preferred, 5,000,000 shares of Parent Common Stock for issuance upon conversion
of the Parent Series D Preferred Stock, 650,000 shares of Parent Common Stock
for issuance upon conversion of outstanding options granted outside Parent's
2000 Equity Incentive Plan (the "Parent Stock Plan"), and 5,257,136 shares of
Parent Common Stock for issuance to officers, directors, employees, sales
representatives and consultants of Parent pursuant to the Parent Stock Plan, of
which 3,687,395 shares are currently subject to outstanding options and
1,569,741 shares are available for future issuance. The Parent Common Stock and
the Parent Series D Preferred Stock, when the Amended and Restated Certificate
of Parent attached hereto as EXHIBIT D (the "Parent Amended and Restated
Certificate") is filed, shall have the rights, preferences, privileges and
restrictions set forth in the Parent Amended and Restated Certificate. There are
no options, warrants (other


                                       32.
<PAGE>

than warrants to purchase 10,000 shares of Parent Common Stock and warrants to
purchase 254,000 shares of Parent Series B Preferred Stock), conversion
privileges or other rights presently outstanding to purchase or otherwise
acquire any authorized but unissued shares of the capital stock or other
securities of Parent, nor any agreements or understandings with respect thereto.
Parent is not a party or subject to any agreement or understanding, and, to
Parent's Knowledge, there is no agreement or understanding between any Persons,
which affects or relates to the voting or giving of consents with respect to any
security or by a director of Parent. Parent is not under any obligation to
register any of its presently outstanding securities or any of its securities
that may hereafter be issued. To Parent's Knowledge, no stockholders of Parent
have entered into any agreements with respect to the voting of capital stock of
Parent.

     3.3 FINANCIAL STATEMENTS.

          (a) Parent has delivered to the Company the following financial
statements and notes (collectively, the "Parent Financial Statements"):

                    (i)  The audited balance sheets of Parent as of December 31,
          1999, and the related audited income statements, statements of
          stockholders' equity and statements of cash flows of Parent for the
          years then ended, together with the notes thereto and the unqualified
          report and opinion of Ernst & Young LLP relating thereto; and

                    (ii) the unaudited balance sheet of Parent as of September
          30, 2000 (the "Unaudited Interim Balance Sheet"), and the related
          unaudited income statement of Parent for the nine months then ended.

          (b) The Parent Financial Statements are accurate and complete in all
material respects and present fairly the financial position of Parent as of the
respective dates thereof and the results of operations and (in the case of the
financial statements referred to in Section 3.5(a)(i)) cash flows of Parent for
the periods covered thereby. The Parent Financial Statements have been prepared
in accordance with generally accepted accounting principles applied on a
consistent basis throughout the periods covered (except that the financial
statements referred to in Section 3.5(a)(ii) do not contain footnotes and are
subject to normal and recurring year-end audit adjustments, which will not,
individually or in the aggregate, be material in magnitude).

          (c) Except as set forth in the Parent Financial Statements, Parent has
no material liabilities, contingent or otherwise, other than (i) liabilities
incurred in the ordinary course of business subsequent to September 30, 2000 and
(ii) obligations under contracts and commitments incurred in the ordinary course
of business and not required under generally accepted accounting principles to
be reflected in the Parent Financial Statements, which, in both cases,
individually or in the aggregate are not material to the financial condition or
operating results of Parent.

     3.4 ACTIONS. Parent has not (i) declared or paid any dividends, or
authorized or made any distribution upon or with respect to any class or series
of its capital stock, (ii) except as may be contemplated by this Agreement,
incurred any indebtedness for money borrowed or incurred any other liabilities
individually in excess of $25,000 or in excess of $50,000 in the aggregate,


                                       33.
<PAGE>

(iii) made any loans or advances to any person, other than ordinary advances for
travel expenses, or (iv) sold, exchanged or otherwise disposed of any of its
assets or rights, other than the sale of its inventory in the ordinary course of
business.

     3.5 TITLE TO PROPERTIES AND ASSETS; LIENS, ETC. Parent has good and
marketable title to all its properties and assets, and is in compliance with the
lease of all material properties leased by it, in each case subject to no
Encumbrances, other than liens for current taxes not yet due and payable. Parent
is not in default under or in breach of any provision of its leases, and Parent
holds valid lease-hold interests in the properties which it leases. Parent's
material properties and assets are in good condition and repair, ordinary wear
and tear excepted, in all material respects.

     3.6 PATENTS, TRADEMARKS, ETC. To the Knowledge of Parent, Parent has
sufficient title and ownership of all patents, trademarks, service marks, trade
names, copyrights, trade secrets, information, proprietary rights and processes
necessary for its business as now conducted, and as proposed to be conducted,
and, to the Knowledge of Parent, without conflict with or infringement of the
rights of others. Parent has not received any communications alleging that
Parent has violated or, by conducting its business as proposed, would violate,
the patents, trademarks, service marks, trade names, copyrights, trade secrets,
information or proprietary or intellectual property rights of any other person
or entity. Parent has no Knowledge of any violation or infringement by a third
party of any of Parent's patents, licenses, trademarks, service marks, trade
names, copyrights, trade secrets or other proprietary rights. Parent has
disclosed trade secrets to other persons solely as required for the conduct of
its business and solely under nondisclosure agreements that are enforceable by
Parent. Parent has at all times maintained reasonable procedures to protect and
have enforced all of its trade secrets.

     3.7 PROPRIETARY INFORMATION AND INVENTIONS AGREEMENTS. Each employee,
consultant and officer of Parent has executed an agreement with Parent regarding
confidentiality and proprietary information substantially in the form or forms
delivered to the counsel for the Company. Parent, after reasonable
investigation, is not aware that any of its employees or consultants is in
violation thereof. All consultants to or vendors of Parent with access to
confidential information of Parent are parties to a written agreement
substantially in the form or forms provided to counsel for the Company under
which, among other things, each such consultant or vendor is obligated to
maintain the confidentiality of confidential information of Parent. Parent,
after reasonable investigation, has no Knowledge that any of its consultants or
vendors are in violation thereof.

     3.8 MATERIAL CONTRACTS AND COMMITMENTS. Part 3.8 of the Parent
Disclosure Schedule sets forth a list of all Contracts to which Parent is a
party or by which it or its assets are bound that (a) involve in excess of
$50,000 aggregating similar agreements or obligations to the same party; (b)
involve to Parent's Knowledge any of the officers, consultants, directors,
employees, or shareholders of Parent or any members of the immediate family of
the foregoing; or (c) obligate Parent to share, license, or develop any product.
True and complete copies of all items set forth on Part 3.8 of the Parent
Disclosure Schedule have been made available to the Major Stockholders.


                                       34.
<PAGE>


       3.9    COMPLIANCE WITH OTHER INSTRUMENTS. Neither Parent nor Merger Sub
is in violation of any term of its respective certificate of incorporation (as
amended) or its respective bylaws (as amended), or in any material respect of
any term or provision of any mortgage, indenture, Contract, judgment or decree,
and to the Parent's Knowledge, neither Parent nor Merger Sub is in violation of
any order, statute, rule or regulation applicable to Parent. The execution,
delivery and performance of and compliance with this Agreement and each of the
other Transaction Agreements, have not resulted and will not result in any
violation of, or conflict with, or constitute a default under any of the
foregoing, or result in the creation of any mortgage, pledge, lien, encumbrance
or charge upon any of the properties or assets of Parent; and there is no such
violation or default which materially and adversely affects the business,
financial condition or results of operations of Parent or any of its properties
or assets. All of the Contracts set forth on Part 3.8 of the Parent Disclosure
Schedule are in full force and effect and constitute legal, valid and binding
obligations of Parent. Parent and, to the Knowledge of Parent, each other party
thereto, has performed in all material respects all obligations required to be
performed by it under the Contracts set forth on Part 3.8 of the Parent
Disclosure Schedule, and no material violation or default exists in respect
thereof, nor any event that with notice or lapse of time, or both, would
constitute a default thereof; on the part of Parent or, to the Knowledge of
Parent, any other party thereto; none of the Contracts set forth on Part 3.8 of
the Parent Disclosure Schedule is currently being renegotiated; and the
validity, effectiveness and continuation of all Contracts set forth on Part 3.8
of the Parent Disclosure Schedule will not be materially adversely affected by
the transactions contemplated by this Agreement or any of the other Transaction
Agreements.

       3.10   VALIDITY OF PARENT CAPITAL STOCK. The Parent Capital Stock, when
issued in compliance with the provisions of this Agreement, will be duly and
validly issued and will be fully paid and nonassessable and free and clear of
all Encumbrances, and the Parent Common Stock issuable upon conversion of the
Parent Series D Preferred Stock will, prior to the Closing, be duly and validly
reserved and, when issued and delivered in compliance with the provisions of the
Amended and Restated Certificate will be duly and validly issued and will be
fully paid and nonassessable and free and clear of all Encumbrances on transfer
other than as set forth in this Agreement and the other Transaction Agreements,
provided, however, that the Parent Capital Stock (and the Parent Common Stock
issuable upon conversion of the Parent Series D Preferred Stock) may be subject
to restrictions on transfer under state and/or federal securities laws. There
are no outstanding rights of first refusal or preemptive rights applicable to
the Parent Capital Stock.

       3.11   GOVERNMENTAL AUTHORIZATIONS. Parent has all Governmental
Authorizations necessary to enable Parent to conduct its business in the manner
in which its business is currently being conducted. Parent is, and at all times
since December 31, 1999 has been, in substantial compliance with the terms and
requirements of all material Governmental Authorizations held by Parent. Since
December 31, 1999, Parent has not received any notice or other communication
from any Governmental Body regarding (a) any actual or possible violation of or
failure to comply with any term or requirement of any Governmental
Authorization, or (b) any actual or possible revocation, withdrawal, suspension,
cancellation, termination or modification of any Governmental Authorization.


                                      35.
<PAGE>

       3.12   TAX RETURNS AND PAYMENTS. Parent has filed all tax returns and
reports as required by law. These returns and reports are true and correct in
all material respects. Parent has paid all taxes and other assessments due.

       3.13   TAX ELECTIONS. Parent has not elected pursuant to the Internal
Revenue Code of 1986, as amended (the "Code"), to be treated as an "S"
corporation or a collapsible corporation pursuant to Section 341(f) or Section
1362(a) of the Code, nor has it made any other elections pursuant to the Code
(other than elections which relate solely to matters of accounting, depreciation
or amortization) which would have a material affect on Parent, its financial
condition, its business as presently conducted or as presently proposed to be
conducted or any of its properties or material assets.

       3.14   EMPLOYEES. To Parent's Knowledge, no employee of Parent is or will
be in violation of any judgment, decree or order of any court or administrative
agency, or any term of any employment contract or any other contract (including
without limitation any covenant not to compete) or agreement relating to the
relationship of any such employee with Parent or any other party because of the
nature of the business conducted or to be conducted by Parent or to the
utilization by the employee of such employee's reasonable efforts with respect
to such business. Parent does not have any collective bargaining agreements
covering any of its employees. To Parent's Knowledge, Parent is not using any
inventions of any of its employees, consultants or officers made before their
employment by Parent. To Parent's Knowledge, no employee, consultant or officer
has taken, removed, or made use of any proprietary documentation, manuals,
products, materials, or any other tangible items from the employee's previous
employers relating to Parent's business. To Parent's Knowledge, no labor union
has sought to represent any of the employees of Parent. There is no strike or
other labor dispute involving Parent pending, or to the Knowledge of Parent,
threatened. To Parent's Knowledge, no officer or key employee intends to
terminate his or her employment with Parent.

       3.15   EMPLOYEE BENEFIT PLANS. Neither Parent nor Merger Sub has any
Employee Benefit Plan as defined in ERISA.

       3.16   ENVIRONMENTAL MATTERS. The business, assets and properties of
Parent are and have been operated and maintained in material compliance with all
applicable Environmental Laws. To Parent's Knowledge, no event has occurred
which, with or without the passage of time or the giving of notice, or both,
would constitute noncompliance by Parent with, or a violation by Parent of, the
Environmental Laws. To Parent's Knowledge, Parent has not caused or permitted to
exist, as a result of an intentional or unintentional act or omission, a
disposal, discharge or release of solid wastes, pollutants or hazardous
substances, on or from any site which currently is or formerly was owned,
leased, occupied or used by it, except where such disposal, discharge or release
was in material compliance with the Environmental Laws.

       3.17   INSURANCE. Parent has in full force and effect fire, casualty and
liability insurance policies with recognized insurers with such coverages as are
sufficient in amount to allow replacement of the tangible properties of Parent
that might be damaged or destroyed.


                                      36.
<PAGE>

       3.18   NO CONFLICT OF INTEREST. Parent is not indebted, directly or
indirectly, to any of its officers or directors or to their respective spouses
or children, in any amount whatsoever other than in connection with expenses or
advances of expenses incurred in the ordinary course of business or relocation
expenses of employees. To Parent's Knowledge, none of Parent's officers or
directors, or any members of their immediate families, are, directly or
indirectly, indebted to Parent (other than in connection with purchases of
Parent's stock) or have any direct or indirect ownership interest in any firm or
corporation with which Parent is affiliated or with which Parent has a business
relationship, or any firm or corporation which competes with Parent, except that
officers, directors and/or shareholders of Parent may own stock in (but not
exceeding two percent of the outstanding capital stock of) any publicly traded
company that may compete with Parent. To Parent's Knowledge, none of Parent's
officers or directors or any members of the immediate families are, directly or
indirectly, interested in any material contract with Parent. Parent is not a
guarantor or indemnitor of any indebtedness of any other Person.

       3.19   LITIGATION, ETC. There are no actions, suits, proceedings or
investigations pending or, to Parent's Knowledge, threatened against Parent or
its properties before any Governmental Body, which, either in any case or in the
aggregate, might result in any material adverse effect on the business,
financial condition, affairs, operations or equity ownership of Parent or any of
its properties or assets, or in any material impairment of the right or ability
of Parent to carry on its business as now conducted or as presently proposed to
be conducted, or in any material liability on the part of Parent, and none which
questions the validity of this Agreement or any of the other Transaction
Agreements or any action taken or to be taken in connection herewith or
therewith. Parent is not a party or subject to the order, writ, judgement,
injunction, decree or other provisions of any Governmental Body. There is no
action, suit, proceeding, or investigation by Parent currently pending or that
Parent intends to initiate.

       3.20   AUTHORITY; BINDING NATURE OF AGREEMENT. Parent and Merger Sub each
has the absolute and unrestricted right, power and authority to enter into and
to perform its respective obligations under this Agreement, the Escrow
Agreements, the Voting Agreements, and the Noncompetition Agreements
(collectively, the "Transaction Agreements"); and the execution, delivery and
performance by Parent and Merger Sub of the Transaction Agreements have been
duly authorized by all necessary action on the part of the Parent and Merger
Sub. This Agreement and each of the other Transaction Agreements to which either
Parent or Merger Sub is a party constitutes the legal, valid and binding
obligation of Parent and/or Merger Sub, as the case may be, enforceable against
Parent and/or Merger Sub, as the case may be, in accordance with their
respective terms, subject to (i) laws of general application relating to
bankruptcy, insolvency and the relief of debtors, and (ii) rules of law
governing specific performance, injunctive relief and other equitable remedies.

       3.21   NON-CONTRAVENTION; CONSENTS. Neither the execution and delivery of
this Agreement by Parent and Merger Sub nor the consummation by Parent and
Merger Sub of the Merger will (a) conflict with or result in any breach of any
provision of the certificate of incorporation or bylaws of Parent or Merger Sub,
(b) result in a default by Parent or Merger Sub under any Contract to which
Parent or Merger Sub is a party, except for any default that has not had and
will not have a Material Adverse Effect on Parent, or (c) result in a violation
by Parent or Merger Sub of any order, writ, injunction, judgment or decree to
which Parent or Merger Sub


                                      37.
<PAGE>

is subject, except for any violation that has not had and will not have a
Material Adverse Effect on Parent. Except as may be required by the Securities
Act, state securities or "blue sky" laws, the DGCL, the HSR Act, any foreign
antitrust law or regulation, Parent is not and will not be required to make any
filing with or give any notice to, or to obtain any Consent from, any Person in
connection with the execution, delivery or performance of this Agreement or the
consummation of the Merger.

       3.22   FINANCIAL CONDITION. Parent was incorporated on May 11, 1998.
Since that time, Parent has only engaged in startup and development activities
and has generated no revenue. Since inception, Parent has been operated only in
the ordinary course of business, and there has not been a Material Adverse
Effect on Parent.

       3.23

       3.24   U.S. REAL PROPERTY HOLDING CORPORATION. Parent is not now, nor
will it be immediately after the Closing, a "United States Real Property Holding
Corporation" as defined in Section 897(c)(2) of the Code and Section 1.897-2(b)
of the regulations promulgated under the Code.

       3.25   INVESTMENT COMPANY ACT. Parent is not an "investment company" nor
is Parent directly or indirectly controlled by or acting on behalf of any person
which is an "Investment Company" within the meaning of the Investment Company
Act of 1940, as amended.

       3.26   NO BROKERS OR FINDERS. Parent has not incurred, and will not
incur, directly or indirectly, any liability for brokerage or finders' fees or
agents' commissions or any similar charges in connection with the transactions
contemplated by this Agreement.

       3.27   FULL DISCLOSURE.

              (a)    No representation or warranty made by Parent or Merger Sub
in this Agreement (including the Parent Disclosure Schedule) (i) contains any
information that is false or misleading with respect to any material fact, or
(ii) omits to state any material fact necessary in order to make such
representations and warranties (in the light of the circumstances under which
such representations, warranties were made) false or misleading.

              (b)    The information supplied by Parent or Merger Sub for
inclusion in the Information Statement (as defined in Section 5.2) will not, as
of the date of the Information Statement or as of the date of the Company
Stockholders' Meeting (as defined in Section 5.3), (i) contain any statement
that is inaccurate or misleading with respect to any material fact, or (ii) omit
to state any material fact necessary in order to make such information (in the
light of the circumstances under which it is provided) not false or misleading.

SECTION 4. CERTAIN COVENANTS OF THE PARTIES

       4.1    ACCESS AND INVESTIGATION. During the period from the date of this
Agreement through the Effective Time (the "Pre-Closing Period"), the Company
shall, and shall cause its Representatives to: (a) provide Parent and Parent's
Representatives with reasonable access to


                                      38.
<PAGE>

the Acquired Corporations' Representatives, personnel and assets and to all
existing books, records, Tax Returns, work papers and other documents and
information relating to the Company; and (b) provide Parent and Parent's
Representatives with copies of such existing books, records, Tax Returns, work
papers and other documents and information relating to the Acquired
Corporations, and with such additional financial, operating and other data and
information regarding the Acquired Corporations, as Parent may reasonably
request.

       4.2    OPERATION OF THE COMPANY'S BUSINESS. During the Pre-Closing
Period:

              (a)    the Company shall (and shall cause each of the other
       Acquired Corporations to) conduct their respective businesses and
       operations in the ordinary course and in substantially the same manner as
       such businesses and operations have been conducted prior to the date of
       this Agreement;

              (b)    the Company shall (and shall cause each of the other
       Acquired Corporations to) use reasonable efforts to preserve intact their
       respective current business organizations, keep available the services of
       their respective current officers and employees and maintain their
       respective relations and good will with all suppliers, customers,
       landlords, creditors, employees and other Persons having business
       relationships with any of the Acquired Corporations;

              (c)    the Company shall (and shall cause each of the other
       Acquired Corporations to) keep in full force all insurance policies
       identified in Part 2.17 of the Company Disclosure Schedule;

              (d)    the Company shall (and shall cause each of the other
       Acquired Corporations to) cause their respective officers to report
       regularly (but in no event less frequently than bi-monthly) to Parent
       concerning the status of the business of each Acquired Corporation;

              (e)    the Company shall use commercially reasonable efforts to
       file an amended and restated certificate of incorporation with the
       Secretary of State for the State of Delaware that provides for a
       liquidation preference in favor of the Company Series A Preferred Stock
       equal in value, in the aggregate, to the Liquidation Consideration (the
       "Company Amended and Restated Certificate");

              (f)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) declare, accrue, set aside or pay any
       dividend or make any other distribution in respect of any shares of
       capital stock, and shall not repurchase, redeem or otherwise reacquire
       any shares of capital stock or other securities (except that the Company
       may repurchase Company Common Stock from former employees pursuant to the
       terms of existing restricted stock purchase agreements);

              (g)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) sell, issue or authorize the issuance of
       (i) any capital stock or other security, (ii) any option or right to
       acquire any capital stock or other security, or (iii) any instrument
       convertible into or exchangeable for any capital stock or other security
       (except


                                      39.
<PAGE>

       that the Company shall be permitted (y) to issue Company Common Stock to
       employees upon the exercise of outstanding Company Options, and (z) to
       issue shares of Company Common Stock upon the conversion of shares of
       Company Preferred Stock);

              (h)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) amend or waive any of its rights under, or
       permit the acceleration of vesting under, (i) any provision of the Stock
       Plan, (ii) any provision of any agreement evidencing any outstanding
       Company Option, or (iii) any provision of any restricted stock purchase
       agreement;

              (i)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) amend or permit the adoption of any
       amendment to the Company's Certificate of Incorporation or Bylaws or
       similar organizational documents of any Acquired Corporation, or effect
       or permit any Acquired Corporation to become a party to any Acquisition
       Transaction, recapitalization, reclassification of shares, stock split,
       reverse stock split or similar transaction (except that the Company may
       issue shares of Company Common Stock upon the conversion of shares of
       Company Series A Preferred Stock);

              (j)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) form any subsidiary or acquire any equity
       interest or other interest in any other Entity;

              (k)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) make any capital expenditure, except for
       capital expenditures that, when added to all other capital expenditures
       made on behalf of the Acquired Corporations during the Pre-Closing
       Period, do not exceed $15,000 per month;

              (l)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) (i) enter into, or permit any of the assets
       owned or used by any Acquired Corporation to become bound by, any
       Contract that is or would constitute a Material Contract, or (ii) amend
       or prematurely terminate, or waive any material right or remedy under,
       any such Contract (except amendment or termination of the Company's
       existing line of credit with that certain Loan Agreement dated February
       1, 1999 among First Union National Bank (the "Bank"), the Company and PPD
       (the "Company Line of Credit");

              (m)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) (i) acquire, lease or license any right or
       other asset from any other Person, (ii) sell or otherwise dispose of, or
       lease or license, any right or other asset to any other Person, or (iii)
       waive or relinquish any right, except for assets acquired, leased,
       licensed or disposed of by the Company pursuant to Contracts that are not
       Material Contracts;

              (n)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) (i) lend money to any Person (except that
       the Company may make


                                      40.
<PAGE>

       routine travel advances to employees in the ordinary course of business
       and may, consistent with its past practices, allow employees to acquire
       Company Common Stock in exchange for promissory notes upon exercise of
       Company Options), or (ii) incur or guarantee any indebtedness for
       borrowed money (except that the Company may make routine borrowings in
       the ordinary course of business under the Company Line of Credit or that
       certain Loan Agreement dated September 22, 2000 among the Company and the
       Major Stockholders (the "Loan Agreement"));

              (o)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) (i) establish, adopt or amend any Employee
       Benefit Plan, (ii) pay any bonus or make any profit-sharing payment, cash
       incentive payment or similar payment to, or increase the amount of the
       wages, salary, commissions, fringe benefits or other compensation or
       remuneration payable to, any of its directors, officers or employees, or
       (iii) hire any new employee whose aggregate annual compensation is
       expected to exceed $50,000;

              (p)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) change any methods of accounting or
       accounting practices of any Acquired Corporation in any material respect;

              (q)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) make any Tax election;

              (r)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) commence or settle any material Legal
       Proceeding;

              (s)    the Company shall not (and shall cause each of the other
       Acquired Corporations not to) agree or commit to take any of the actions
       described in clauses "(f)" through "(f)" above.

Notwithstanding the foregoing, the Company may take any action described in
clauses "(f)" through "(s)" above if Parent gives its prior written consent to
the taking of such action by the Company, which consent will not be unreasonably
withheld (it being understood that Parent's withholding of consent to any action
will not be deemed unreasonable if Parent determines in good faith that the
taking of such action would not be in the best interests of Parent or would not
be in the best interests of the Company); PROVIDED, HOWEVER, that Parent's
consent shall be deemed to have been granted if Parent fails to reply to a
written request from the Company to take any action described in clauses "(e)"
through "(r)" above within five days after receipt of such written request.

       4.3    NOTIFICATION; UPDATES TO COMPANY DISCLOSURE SCHEDULE.

              (a)    During the Pre-Closing Period, the Company shall promptly
notify Parent in writing of:

                     (i)    the discovery by any Acquired Corporation of any
       event, condition, fact or circumstance that occurred or existed on or
       prior to the date of this


                                      41.
<PAGE>

       Agreement and that caused or constitutes an inaccuracy in or breach of
       any representation or warranty made by the Company in this Agreement;

                     (ii)   any event, condition, fact or circumstance that
       occurs, arises or exists after the date of this Agreement and that would
       cause or constitute an inaccuracy in or breach of any representation or
       warranty made by the Company in this Agreement if (A) such representation
       or warranty had been made as of the time of the occurrence, existence or
       discovery of such event, condition, fact or circumstance, or (B) such
       event, condition, fact or circumstance had occurred, arisen or existed on
       or prior to the date of this Agreement;

                     (iii)  any breach of any covenant or obligation of the
       Company; and

                     (iv)   any event, condition, fact or circumstance that
       would make the timely satisfaction of any of the conditions set forth in
       Section 6 or Section 7 impossible or unlikely.

              (b)    If any event, condition, fact or circumstance that is
required to be disclosed pursuant to Section 4.3(a) requires any change in the
Company Disclosure Schedule, or if any such event, condition, fact or
circumstance would require such a change assuming the Company Disclosure
Schedule were dated as of the date of the occurrence, existence or discovery of
such event, condition, fact or circumstance, then the Company shall promptly
deliver to Parent an update to the Company Disclosure Schedule specifying such
change. No such update shall be deemed to supplement or amend the Company
Disclosure Schedule for the purpose of (i) except as set forth in Section
9.2(a), determining the accuracy of any of the representations and warranties
made by the Company in this Agreement, or (ii) determining whether any of the
conditions set forth in Section 6 has been satisfied.

       4.4    NOTIFICATION; UPDATES TO PARENT DISCLOSURE SCHEDULE.

              (a)    During the Pre-Closing Period, Parent shall promptly notify
the Company in writing of:

                     (i)    the discovery by Parent of any event, condition,
       fact or circumstance that occurred or existed on or prior to the date of
       this Agreement and that caused or constitutes an inaccuracy in or breach
       of any representation or warranty made by Parent and Merger Sub in this
       Agreement;

                     (ii)   any event, condition, fact or circumstance that
       occurs, arises or exists after the date of this Agreement and that would
       cause or constitute an inaccuracy in or breach of any representation or
       warranty made by Parent and Merger Sub in this Agreement if (A) such
       representation or warranty had been made as of the time of the
       occurrence, existence or discovery of such event, condition, fact or
       circumstance, or (B) such event, condition, fact or circumstance had
       occurred, arisen or existed on or prior to the date of this Agreement;


                                      42.
<PAGE>

                     (iii)  any breach of any covenant or obligation of Parent
       or Merger Sub; and

                     (iv)   any event, condition, fact or circumstance that
       would make the timely satisfaction of any of the conditions set forth in
       Section 6 or Section 7 impossible or unlikely.

       If any event, condition, fact or circumstance that is required to be
disclosed pursuant to Section 4.4(a) requires any change in the Parent
Disclosure Schedule, or if any such event, condition, fact or circumstance would
require such a change assuming the Parent Disclosure Schedule were dated as of
the date of the occurrence, existence or discovery of such event, condition,
fact or circumstance, then Parent shall promptly deliver to the Company an
update to the Parent Disclosure Schedule specifying such change. No such update
shall be deemed to supplement or amend the Parent Disclosure Schedule for the
purpose of (i) except as set forth in Section 9.2(b), determining the accuracy
of any of the representations and warranties made by Parent and Merger Sub in
this Agreement, or (ii) determining whether any of the conditions set forth in
Section 7 has been satisfied.

       4.5    OPERATION OF PARENT'S BUSINESS. DURING THE PRE-CLOSING PERIOD:

              (a)    Parent shall (and shall cause each of its Subsidiaries to)
       conduct their respective businesses and operations in the ordinary course
       and in substantially the same manner as such businesses and operations
       have been conducted prior to the date of this Agreement (it being
       understood, however, that Parent may continue preparations for the
       initial public offering of Parent Common Stock);

              (b)    Parent shall (and shall cause each of its respective
       Subsidiaries to) use reasonable efforts to preserve intact their
       respective current business organizations, keep available the services of
       their respective current officers and employees and maintain their
       respective relations and good will with all suppliers, customers,
       landlords, creditors, employees and other Persons having business
       relationships with any of Parent and/or any of its Subsidiaries;

              (c)    Parent shall use commercially reasonable efforts to file
       the Amended and Restated Certificate as soon as possible;

              (d)    Parent shall use commercially reasonable efforts to ensure
       that, as of immediately after the Closing, PPD will be permitted to
       appoint one member of the board of directors of Parent.

              (e)    Parent shall not declare, accrue, set aside or pay any
       dividend or make any other distribution in respect of any shares of
       Parent's capital stock, and shall not repurchase, redeem or otherwise
       reacquire any shares of Parent's capital stock or other securities
       (except that Parent may repurchase Parent Common Stock from former
       employees pursuant to the terms of existing restricted stock purchase
       agreements);


                                      43.
<PAGE>

              (f)    Parent shall not amend or permit the adoption of any
       amendment to the Restated Certificate or Parent's Bylaws that would have
       the effect of diminishing the rights, preferences or privileges of the
       Parent Series D Preferred Stock as set forth in the Restated Certificate.

Notwithstanding the foregoing, Parent may take any action described in clauses
"(e)" or "(f)" if the Company gives its prior written consent to the taking of
such action by Parent, which consent will not be unreasonably withheld (it being
understood that the Company's withholding of consent to any action will not be
deemed unreasonable if the Company determines in good faith that the taking of
such action would not be in the best interests of the Company); PROVIDED,
HOWEVER, that the Company's consent shall be deemed to have been granted if the
Company fails to reply to a written request from Parent to take any action
described in clauses "(e)" or "(f)" above within five days after receipt of such
written request

       4.6    NO NEGOTIATION. During the Pre-Closing Period, the Company shall
not (and shall cause each of the other Acquired Corporations not to), directly
or indirectly:

              (a)    solicit or encourage the initiation of any inquiry,
       proposal or offer from any Person (other than Parent) relating to a
       possible Acquisition Transaction;

              (b)    participate in any discussions or negotiations or enter
       into any agreement with, or provide any non-public information to, any
       Person (other than Parent) relating to or in connection with a possible
       Acquisition Transaction; or

              (c)    consider, entertain or accept any proposal or offer from
       any Person (other than Parent) relating to a possible Acquisition
       Transaction.

The Company shall promptly notify Parent in writing of any material inquiry,
proposal or offer relating to a possible Acquisition Transaction that is
received by the Company during the Pre-Closing Period.

SECTION 5. ADDITIONAL COVENANTS OF THE PARTIES

       5.1    FILINGS AND CONSENTS. As promptly as practicable after the
execution of this Agreement, each party to this Agreement (a) shall make all
filings (if any) and give all notices (if any) required to be made and given by
such party in connection with the Merger and the other transactions contemplated
by this Agreement, and (b) shall use all commercially reasonable efforts to
obtain all Consents (if any) required to be obtained (pursuant to any applicable
Legal Requirement or Contract, or otherwise) by such party in connection with
the Merger and the other transactions contemplated by this Agreement. The
Company shall (upon request) promptly deliver to Parent a copy of each such
filing made, each such notice given and each such Consent obtained by the
Company during the Pre-Closing Period.

       5.2    COMPANY STOCKHOLDERS' MEETING. As promptly as practicable after
the execution of this Agreement, the Company and Parent shall jointly prepare an
Information Statement relating to the adoption of this Agreement and the
approval of the transactions contemplated hereby by the Company's stockholders
and the exercise of appraisal rights in connection


                                      44.
<PAGE>

therewith (the "Information Statement"). The Company shall provide and include
in the Information Statement such information relating to the Company and its
stockholders as may be required pursuant to the provisions of applicable
securities and corporate laws (including, without limitation, Rule 502 under the
Securities Act). The Company shall, in accordance with its Certificate of
Incorporation and Bylaws and the applicable requirements of the Delaware General
Corporation Law, call and hold a special meeting of its stockholders as promptly
as practicable, and in any event no later than December 20, 2000, for the
purpose of permitting them to consider and to vote upon and adopt this Agreement
and approve the transactions contemplated hereby (the "Company Stockholders'
Meeting"). The Company shall cause a copy of the Information Statement to be
delivered to each stockholder of the Company who is entitled to vote on the
adoption of this Agreement and approval of the transactions contemplated hereby.
As promptly as practicable after the delivery of copies of the Information
Statement to all stockholders entitled to vote at the Company Stockholders'
Meeting, the Company shall take all actions necessary (i) to solicit from each
of such stockholders a proxy in favor of the adoption of this Agreement and the
approval of the transactions contemplated hereby and (ii) to cause each of such
stockholders to execute and deliver to Parent a Stockholder Representation
Letter in a form to be mutually agreed upon by the parties hereto. In lieu of
calling and holding the Company Stockholders' Meeting, the Company may solicit
written consents (to be effective on or prior to December 20, 2000) in
accordance with its certificate of incorporation and bylaws and the applicable
requirements of the Delaware General Corporation Law. Parent will reasonably
cooperate with the Company with respect to the matters set forth in this Section
5.2. Parent will promptly provide all information relating to its business or
operations necessary for inclusion in the Information Statement to satisfy all
requirements of applicable state and federal securities and corporate laws.

       5.3    PUBLIC ANNOUNCEMENTS. During the Pre-Closing Period, (a) Neither
Parent nor the Company shall (and Parent and the Company shall not permit any of
their respective Representatives to, and the Company shall use commercially
reasonable efforts to cause the Major Stockholders to) issue any press release
or make any public statement regarding this Agreement or the Merger, or
regarding any of the other transactions contemplated by this Agreement, without
the prior written consent of the Company or Parent, as the case may be, and (b)
Parent and the Company will use reasonable efforts to consult with one another
(and the Company shall use commercially reasonable efforts to cause the Major
Stockholders to consult with Parent) prior to issuing any press release or
making any public statement regarding the Merger.

       5.4    REASONABLE EFFORTS. During the Pre-Closing Period, (a) the Company
shall use commercially reasonable efforts to cause the conditions set forth in
Section 6 to be satisfied on a timely basis, and (b) Parent and Merger Sub shall
use commercially reasonable efforts to cause the conditions set forth in Section
7 to be satisfied on a timely basis.

       5.5    TAX MATTERS. Prior to the Closing, Parent, Merger Sub and the
Company shall execute and deliver, to Cooley Godward LLP and to Heller Ehrman
White & McAuliffe LLP, tax representation letters in substantially the form of
EXHIBIT E. Parent, Merger Sub and the Company shall each confirm to Cooley
Godward LLP and to Heller Ehrman White & McAuliffe LLP the accuracy and
completeness as of the Effective Time and thereafter, where relevant, of


                                      45.
<PAGE>

the tax representation letters delivered pursuant to the immediately preceding
sentence. Parent and the Company shall use commercially reasonable efforts prior
to the Effective Time to cause the Merger to qualify as a tax-free
reorganization under Section 368(a)(1) of the Code. Following delivery of the
tax representation letters pursuant to the first sentence of this Section 5.6,
each of Parent and the Company shall use its commercially reasonable efforts to
cause Cooley Godward LLP and Heller Ehrman White & McAuliffe LLP, respectively,
to deliver to it a tax opinion satisfying the requirements of Section 6.5(h)
hereof and Section 7.3(b) hereof. In rendering such opinions, each of such
counsel shall be entitled to rely on the tax representation letters referred to
in this Section 5.6. The parties hereto shall report the Merger as a
reorganization within the meaning of Section 368(a) of the Code, and neither
Parent, Merger Sub nor the Company shall take any action prior to or following
the Closing that would reasonably be expected to cause the Merger to fail to
qualify as a reorganization.

       5.6    NONCOMPETITION AGREEMENTS. The Company shall use commercially
reasonable efforts to cause each of the Major Stockholders to execute and
deliver to Parent prior to the Closing a Noncompetition Agreement in the form of
EXHIBIT F.

       5.7    EMPLOYMENT AGREEMENTS. The Company shall use commercially
reasonable efforts to cause each of the individuals identified on EXHIBIT G to
execute and deliver to Parent prior to the Closing an Employment Agreement in
the form of EXHIBIT H.

       5.8    RELEASES. The Company shall use commercially reasonable efforts to
cause each of the Company stockholders to execute and deliver to Parent at the
Closing a Release in the form of EXHIBIT I.

       5.9    UNDERWRITER LOCKUP AGREEMENTS. The Company shall use commercially
reasonable efforts to cause each of the Company stockholders to execute and
deliver to Parent prior to the Closing an Underwriter Lockup Agreement in the
form of EXHIBIT J.

       5.10   AMENDMENT/CLARIFICATION OF EXISTING AGREEMENTS; PAYOFF OF COMPANY
LINE OF CREDIT.

              (a)    The Company shall execute and deliver, and shall use
commercially reasonable efforts to cause the other parties to such agreements to
execute and deliver: (1) the Amended and Restated Distributor Agreement between
the Company and PPD dated February 1, 1999, as amended attached hereto as
EXHIBIT K; and (2) the Amended and Restated Technology Transfer and License
Agreement between the Company and Axys dated February 1, 1999, as amended
attached hereto as EXHIBIT L. The Company shall execute and deliver, and shall
use commercially reasonable efforts to cause PPD to execute and deliver, (1) the
clarification letter to the PPD/PPGx Joint Development Agreement attached hereto
as EXHIBIT M and (2) the real property indemnity letter attached hereto as
EXHIBIT N. The Company shall execute and deliver, and shall use commercially
reasonable efforts to cause Axys to execute and deliver, (1) the covenant not to
sue agreement attached hereto as EXHIBIT O and (2) the assignment letter
attached hereto as EXHIBIT P.


                                      46.
<PAGE>

              (b)    Parent shall use commercially reasonable efforts to execute
and deliver (and the Company shall use commercially reasonable efforts to cause
the Major Stockholders to execute and deliver): (1) that certain Amended and
Restated Investor Rights Agreement attached hereto as EXHIBIT Q; and (2) that
certain Co-Sale Agreement attached hereto as EXHIBIT R.

              (c)    The Company shall use commercially reasonable efforts to
cause the Company's indebtedness existing as of immediately prior to the Closing
to the Bank to be repaid and the indebtedness due and payable to the Major
Stockholders under the Loan Agreement to be contributed to the capital of the
Company.

       5.11   TERMINATION OF CERTAIN AGREEMENTS.

              (a)    The Company shall use commercially reasonable efforts to
ensure that the Investor Rights Agreement of the Company dated February 1, 1999
and the Registration Rights Agreement of the Company dated February 1, 1999 are
terminated prior to the Closing:

              (b)    The Company shall use commercially reasonable efforts to
ensure that all provisions in Contracts that provide any Person with rights of
any nature with respect to the board of directors of the Company (except as
provided generally by the Company's Certificate of Incorporation and Bylaws (or
similar organizational documents) or by applicable Legal Requirements) are
validly and effectively terminated as of the Effective Time.

       5.12   FIRPTA MATTERS. At the Closing, (a) the Company shall deliver to
Parent a statement (in such form as may be reasonably requested by counsel to
Parent) conforming to the requirements of Section 1.897 - 2(h)(1)(i) of the
United States Treasure Regulations, and (b) the Company shall deliver to the
Internal Revenue Service the notification required under Section 1.897 - 2(h)(2)
of the United States Treasury Regulations.

       5.13   EMPLOYEE AND RELATED MATTERS.

              (a)    The Company shall take any and all actions that are
necessary prior to the Closing to terminate its status as a participating
employer/sponsor of the AXYS qualified retirement plan (the "AXYS 401(k) Plan")
so that the employees of the Acquired Corporations will no longer be eligible to
participate in the AXYS 401(k) Plan as of a date that is prior to the Closing
Date. Those employees of the Acquired Corporations that continue to be employees
of Parent or any of its affiliates, including the Company, following the Closing
would, subject to any necessary transition period and the terms of such plans,
be eligible to participate in Parent's health, vacation, employee stock
purchase, stock option, 401(k) and other plans, to the same extent as comparably
situated employees of Parent and would receive credit under Parent's benefit
plans for service as an employee of the Acquired Corporations. Parent shall
exercise commercially reasonable efforts to minimize the duration of any
necessary transition period and to amend or replace Parent's existing plans as
Parent, in its reasonable discretion believes necessary to comply with this
Section 5.13(a).

              (b)    At the Closing, the Company shall terminate its 2000
Incentive Compensation Plan and its 2000 Merit Compensation Plan, and shall
ensure that no employee or former employee of any Acquired Corporation has any
rights under any of such Plans and that


                                      47.
<PAGE>

any liabilities of the Acquired Corporations under such Plans (including any
such liabilities relating to services performed prior to the Closing) are fully
extinguished at no cost to the Acquired Corporations.

SECTION 6. CONDITIONS PRECEDENT TO OBLIGATIONS OF PARENT AND MERGER SUB

              The obligations of Parent and Merger Sub to effect the Merger and
otherwise consummate the transactions contemplated by this Agreement are subject
to the satisfaction, at or prior to the Closing, of each of the following
conditions:

       6.1    ACCURACY OF REPRESENTATIONS. Each of the representations and
warranties made by the Company in this Agreement and in each of the other
agreements and instruments delivered to Parent in connection with the
transactions contemplated by this Agreement shall have been accurate in all
material respects as of the date of this Agreement (except to the extent that
such representations and warranties relate to a specific date, in which case
such representations and warranties shall be accurate on and as of such specific
date), and shall be accurate in all material respects as of the Closing as if
made at the Closing (except to the extent that such representations and
warranties relate to a specific date, in which case such representations and
warranties shall be accurate on and as of such specific date); PROVIDED,
HOWEVER, that for purposes of determining the accuracy of such representations
and warranties for purposes of this Section 6.1, all "Material Adverse Effect,"
other materiality qualifications and other similar qualifications contained in
such representations and warranties shall be disregarded.

       6.2    PERFORMANCE OF COVENANTS. All of the covenants and obligations
that the Company is required to comply with or to perform at or prior to the
Closing shall have been complied with and performed in all material respects.

       6.3    STOCKHOLDER APPROVAL. The adoption of this Agreement and the
approval of the transactions contemplated hereby shall have been duly approved
by the affirmative vote of all of the shares of Company Series A Preferred Stock
and at least 95% of the shares of Company Common Stock entitled to vote with
respect thereto.

       6.4    CONSENTS. All Consents required to be obtained in connection with
the Merger and the other transactions contemplated by this Agreement (including
the Consents identified in Part 2.21 of the Company Disclosure Schedule) shall
have been obtained and shall be in full force and effect.

       6.5    AGREEMENTS AND DOCUMENTS. Parent and the Company shall have
received the following agreements and documents, each of which shall be in full
force and effect:

              (a)    Employment Agreements in the form of EXHIBIT H, executed by
       the individuals identified on EXHIBIT G;

              (b)    Noncompetition Agreements in the form of EXHIBIT F,
       executed by the Major Stockholders;


                                      48.
<PAGE>

              (c)    Releases in the form of EXHIBIT I, executed by the Major
       Stockholders;

              (d)    the statement referred to in Section 5.12, executed by the
       Company;

              (e)    the documents listed as Exhibits to this Agreement set
       forth in Section 5.10(a);

              (f)    a legal opinion of Heller Ehrman White & McAuliffe LLP,
       dated as of the Closing Date, in the form of EXHIBIT S;

              (g)    a legal opinion of Cooley Godward LLP (or, if Cooley
       Godward LLP for any reason does not render such legal opinion, a legal
       opinion of Heller Ehrman White & McAuliffe LLP), dated as of the Closing
       Date, to the effect that the Merger will constitute a reorganization
       within the meaning of Section 368 of the Code (it being understood that,
       in rendering such opinion, such counsel may rely upon the tax
       representation letters referred to in Section 5.5);

              (h)    written resignations of all directors and officers of the
       Company, effective as of the Effective Time;

              (i)    an Underwriter Lock-up Agreement in the form of EXHIBIT J,
       executed by each of the Major Stockholders;

              (j)    an Escrow Agreement in the form of EXHIBIT C, executed by
       the Stockholders' Agent and the Stockholders' Agent;

              (k)    the Amended and Restated Investor Rights Agreement in the
       form of EXHIBIT Q, executed by each of the Major Stockholders;

              (l)    the Amended and Restated Co-Sale Agreement in the form of
       EXHIBIT R, executed by each of the Major Stockholders; and

              (m)    a certificate executed by the Chief Executive Officer of
       the Company and containing the representation and warranty of each of
       them that the conditions set forth in Sections 6.1, 6.2, 6.3, 6.4, 6.6
       and 6.8 have been duly satisfied (the "Company Closing Certificate").

       6.6    ABSENCE OF MATERIAL ADVERSE EFFECT. Since the date of this
Agreement, there shall not have occurred any Material Adverse Effect on the
Company, and no event shall have occurred or circumstance shall exist that, in
combination with any other events or circumstances, could reasonably be expected
to have a Material Adverse Effect on the Company.

       6.7    HSR ACT. The waiting period applicable to the consummation of the
exercise of the PPD Call, as such term is defined in the Company's Investor
Rights Agreement, under the HSR Act shall have expired or been terminated, and
there shall not be in effect any voluntary agreement between PPD and the Federal
Trade Commission or the Department of Justice pursuant to which PPD has agreed
not to consummate the exercise of the PPD Call for any


                                      49.
<PAGE>

period of time; any similar waiting period applicable to the Merger or the
exercise of the PPD Call under any applicable foreign antitrust law or
regulation shall have expired or been terminated; and any Consent required under
any applicable foreign antitrust law or regulation in connection with the Merger
or the exercise of the PPD call shall have been obtained.

       6.8    FIRPTA COMPLIANCE. The Company shall have filed with the Internal
Revenue Service the notification referred to in Section 5.12.

       6.9    NO RESTRAINTS. No temporary restraining order, preliminary or
permanent injunction or other order preventing the consummation of the Merger
shall have been issued by any court of competent jurisdiction and remain in
effect, and there shall not be any Legal Requirement enacted or deemed
applicable to the Merger that makes consummation of the Merger illegal.

       6.10   NO LEGAL PROCEEDINGS. No Person shall have commenced or threatened
to commence any Legal Proceeding (a) challenging or seeking the recovery of a
material amount of damages in connection with the Merger, (b) seeking to
prohibit or limit the exercise by Parent of any material right pertaining to its
ownership of stock of the Surviving Corporation, or (c) claiming to own any
capital stock of the Company, or option or other right to acquire capital stock
of the Company or any other Acquired Corporation, or right to receive
consideration as a result of the Merger.

       6.11   EMPLOYEES. Parent shall have received assurances reasonably
satisfactory to it that none of the individuals identified on EXHIBIT G shall
have ceased to be employed by, or expressed an intention to terminate their
employment with, the Company.

       6.12   TERMINATION OF CERTAIN AGREEMENTS. The Company shall have provided
Parent with evidence, reasonably satisfactory to Parent, as to the termination
of those agreements listed in Section 5.11.

       6.13   CLOSING OF SERIES C INVESTMENT. Parent and PPD shall have closed
the acquisition of Parent Series C Preferred Stock by PPD (the "Series C
Investment").

       6.14   AMENDED AND RESTATED CERTIFICATE. The Amended and Restated
Certificate shall have been accepted for filing by the Secretary of State of the
State of Delaware.

       6.15   COMPANY AMENDED AND RESTATED CERTIFICATE. The Company Amended and
Restated Certificate shall have been accepted for filing by the Secretary of
State of the State of Delaware.

SECTION 7. CONDITIONS PRECEDENT TO OBLIGATIONS OF THE COMPANY

       The obligations of the Company to effect the Merger and otherwise
consummate the transactions contemplated by this Agreement are subject to the
satisfaction, at or prior to the Closing, of the following conditions:


                                      50.
<PAGE>

       7.1    ACCURACY OF REPRESENTATIONS. Each of the representations and
warranties made by Parent and Merger Sub in this Agreement shall have been
accurate in all material respects as of the date of this Agreement (except to
the extent that such representations and warranties relate to a specific date,
in which case such representations and warranties shall be accurate on and as of
such specific date), and shall be accurate in all material respects as of the
Closing as if made at the Closing (except to the extent that such
representations and warranties relate to a specific date, in which case such
representations and warranties shall be accurate on and as of such specific
date); PROVIDED, HOWEVER, that for purposes of determining the accuracy of such
representations and warranties for purposes of this Section 7.1, all "Material
Adverse Effect," other materiality qualifications and other similar
qualifications contained in such representations and warranties shall be
disregarded.

       7.2    PERFORMANCE OF COVENANTS. All of the covenants and obligations
that Parent and Merger Sub are required to comply with or to perform at or prior
to the Closing shall have been complied with and performed in all material
respects.

       7.3    DOCUMENTS. The Company shall have received the following
documents:

              (a)    a legal opinion of Cooley Godward LLP, dated as of the
       Closing Date, in the form of EXHIBIT T;

              (b)    a legal opinion of Heller Ehrman White & McAuliffe LLP (or,
       if Heller Ehrman White & McAuliffe LLP for any reason does not render
       such legal opinion, a legal opinion of Cooley Godward LLP), dated as of
       the Closing Date, to the effect that the Merger will constitute a
       reorganization within the meaning of Section 368 of the Code (it being
       understood that, in rendering such opinion, such counsel may rely upon
       the tax representation letters referred to in Section 5.6; and

              (c)    an Escrow Agreement in the form of EXHIBIT C, executed by
       Parent and the Escrow Agent, which Escrow Agreement shall be in full
       force and effect.

       7.4    NO RESTRAINTS. No temporary restraining order, preliminary or
permanent injunction or other order preventing the consummation of the Merger
shall have been issued by any court of competent jurisdiction and remain in
effect, and there shall not be any Legal Requirement enacted or deemed
applicable to the Merger that makes consummation of the Merger illegal.

       7.5    ABSENCE OF MATERIAL ADVERSE EFFECT. Since the date of this
Agreement, there shall not have occurred any Material Adverse Effect on Parent,
and no event shall have occurred or circumstance shall exist that, in
combination with any other events or circumstances, could reasonably be expected
to have a Material Adverse Effect on Parent.

       7.6    HSR ACT. The waiting period applicable to the consummation of the
exercise of the PPD Call under the HSR Act shall have expired or been
terminated, and there shall not be in effect any voluntary agreement between PPD
and the Federal Trade Commission or the Department of Justice pursuant to which
PPD has agreed not to consummate the exercise of the PPD Call for any period of
time; any similar waiting period applicable to the Merger or the


                                      51.
<PAGE>

exercise of the PPD Call under any applicable foreign antitrust law or
regulation shall have expired or been terminated; and any Consent required under
any applicable foreign antitrust law or regulation in connection with the Merger
or the exercise of the PPD Call shall have been obtained.

       7.7    AMENDED AND RESTATED CERTIFICATE. The Amended and Restated
Certificate shall have been accepted for filing by the Secretary of State of the
State of Delaware.

       7.8    DIRECTOR APPOINTMENT. The Company shall have received evidence
reasonably satisfactory to it that immediately after the Closing, PPD shall have
the right to appoint one member of the board of directors of Parent.

       7.9    COMPANY AMENDED AND RESTATED CERTIFICATE. The Company Amended and
Restated Certificate shall have been accepted for filing by the Secretary of
State of the State of Delaware.

       7.10   CLOSING OF SERIES C INVESTMENT. Parent and PPD shall have closed
the Series C Investment.

SECTION 8. TERMINATION

       8.1    TERMINATION EVENTS. This Agreement may be terminated prior to the
Closing:

              (a)    by Parent if Parent reasonably determines that the timely
       satisfaction of any condition set forth in Section 6 has become
       impossible (other than as a result of any failure on the part of Parent
       or Merger Sub to comply with or perform any covenant or obligation of
       Parent or Merger Sub set forth in this Agreement);

              (b)    by the Company if the Company reasonably determines that
       the timely satisfaction of any condition set forth in Section 7 has
       become impossible (other than as a result of any failure on the part of
       the Company to comply with or perform any covenant or obligation set
       forth in this Agreement or in any other agreement or instrument delivered
       to Parent);

              (c)    by Parent if the Closing has not taken place on or before
       January 15, 2001 (other than as a result of any failure on the part of
       Parent to comply with or perform any covenant or obligation of Parent set
       forth in this Agreement);

              (d)    by the Company if the Closing has not taken place on or
       before January 15, 2001 (other than as a result of the failure on the
       part of the Company to comply with or perform any covenant or obligation
       set forth in this Agreement or in any other agreement or instrument
       delivered to Parent);

              (e)    by either Parent or the Company if a Governmental Body
       shall have issued a final and nonappealable order, decree or ruling, or
       shall have taken any other action, having the effect of permanently
       restraining, enjoining or otherwise prohibiting the Merger; or


                                      52.
<PAGE>

              (f)    by the mutual consent of Parent and the Company.

       8.2    TERMINATION PROCEDURES. If Parent wishes to terminate this
Agreement pursuant to Section 8.1(a), Section 8.1(c) or Section 8.1(e), Parent
shall deliver to the Company a written notice stating that Parent is terminating
this Agreement and setting forth a brief description of the basis on which
Parent is terminating this Agreement. If the Company wishes to terminate this
Agreement pursuant to Section 8.1(b), Section 8.1(d) or Section 8.1(e), the
Company shall deliver to Parent a written notice stating that the Company is
terminating this Agreement and setting forth a brief description of the basis on
which the Company is terminating this Agreement.

       8.3    EFFECT OF TERMINATION. If this Agreement is terminated pursuant to
Section 8.1, all further obligations of the parties under this Agreement shall
terminate; PROVIDED, HOWEVER, that: (a) neither the Company nor Parent shall be
relieved of any obligation or liability arising from any prior breach by such
party of any provision of this Agreement; (b) the parties shall, in all events,
remain bound by and continue to be subject to the provisions set forth in
Section 10; and (c) the Company shall, in all events, remain bound by and
continue to be subject to Section 5.4.

SECTION 9. INDEMNIFICATION, ETC.

       9.1    SURVIVAL OF REPRESENTATIONS, ETC.

              (a)    The representations and warranties made by the parties
(including the representations and warranties set forth in Section 2 and Section
3) shall survive until the February 28, 2002 (the "Termination Date"); PROVIDED,
HOWEVER, that if, at any time prior to the Termination Date, any Parent
Indemnitee or Stockholder Indemnitee (acting in good faith) delivers to the
Stockholders' Agent or Parent, as the case may be, a written notice alleging the
existence of an inaccuracy in or a breach of any of the representations and
warranties made by the Company, on the one hand, or Parent and Merger Sub, on
the other hand, (and setting forth in reasonable detail the basis for such
Indemnitee's belief that such an inaccuracy or breach may exist) and asserting a
claim for recovery under Section 9.2 based on such alleged inaccuracy or breach,
then the claim asserted in such notice shall survive the Termination Date until
such time as such claim is fully and finally resolved.

              (b)    The representations, warranties, covenants and obligations
of the Company, on the one hand, and Parent and Merger Sub, on the other hand,
and the rights and remedies that may be exercised by the Indemnitees, shall not
be limited or otherwise affected by or as a result of any information furnished
to, or any investigation made by or knowledge of, any of the Indemnitees or any
of their Representatives.

              (c)    For purposes of this Agreement, (i) each statement or other
item of information set forth in the Company Disclosure Schedule or in any
update to the Company Disclosure Schedule shall be deemed to be a representation
and warranty made by the Company in this Agreement and (ii) each statement or
other item of information set forth in the Parent


                                      53.
<PAGE>

Disclosure Schedule or in any update to the Parent Disclosure Schedule shall be
deemed to be a representation and warranty made by Parent and Merger Sub in this
Agreement.

       9.2    INDEMNIFICATION.

              (a)    INDEMNIFICATION BY MAJOR STOCKHOLDERS. From and after the
Closing (but subject to Section 9.1(a), 9.3 and 9.4), the Major Stockholders,
jointly and severally shall hold harmless and indemnify each of the Parent
Indemnitees from and against, and shall compensate and reimburse each of the
Parent Indemnitees for, any Damages that are suffered or incurred by any of the
Parent Indemnitees or to which any of the Parent Indemnitees may otherwise
become subject (regardless of whether or not such Damages relate to any
third-party claim) and that arise from or as a result of, or are directly or
indirectly connected with: (i) any inaccuracy in or breach of any representation
or warranty made by the Company in Section 2 of this Agreement (without giving
effect to any "Material Adverse Effect" or other materiality qualification or
any similar qualification contained or incorporated directly in such
representation or warranty, and without giving effect to any update to the
Company Disclosure Schedule delivered by the Company to Parent prior to the
Closing); (ii) any inaccuracy in or breach of any representation or warranty
made by the Company in Section 2 as if such representation and warranty had been
made on and as of the Closing Date (except for such representations and
warranties that address matters only as of a particular time, which need only be
accurate as of such time) (after having given effect to any updates to the
Company Disclosure Schedule delivered to Parent prior to the Closing pursuant to
Section 4.3(b), but without giving effect to any "Material Adverse Effect" or
other materiality qualification or any similar qualification contained or
incorporated directly in such representation or warranty); (iii) any breach of
any covenant or obligation of the Company in this Agreement to be performed
prior to the Closing (including, without limitation, the covenants set forth in
Sections 4 and 5); (iv) any claim or demand made by the Company's legal counsel,
accountants, the Company Financial Advisors or other advisors with respect to
fees, costs or expenses payable to them in connection with the transactions
contemplated by this Agreement to the extent that such fees, costs and expenses
constitute Excess Transaction Expenses and exceed the Excess Transaction
Expenses, if any, used in determining the Parent Share Number in Section 1.5; or
(v) any Legal Proceeding relating to (Y) any inaccuracy or breach of the type
referred to in clause "(i)," "(ii)" or "(iii)" above or (Z) any claim or demand
of the type referred to in clause "(iv)" above (including with respect to each
of clause "(Y)" and clause "(Z)" of this clause "(v)," any Legal Proceeding
commenced by any Parent Indemnitee for the purpose of enforcing any of its
rights under this Section 9).

              (b)    INDEMNIFICATION BY PARENT. From and after the Closing (but
subject to Section 9.1(a), 9.3 and 9.4), Parent shall hold harmless and
indemnify each of the Stockholder Indemnitees from and against, and shall
compensate and reimburse each of the Stockholder Indemnitees for, any Damages
that are suffered or incurred by any of the Stockholder Indemnitees or to which
any of the Stockholder Indemnitees may otherwise become subject (regardless of
whether or not such Damages relate to any third-party claim) and that arise from
or as a result of, or are directly or indirectly connected with: (i) any
inaccuracy in or breach of any representation or warranty made by Parent and
Merger Sub in Section 3 of this Agreement (without giving effect to any
"Material Adverse Effect" or other materiality qualification or any


                                      54.
<PAGE>

similar qualification contained or incorporated directly in such representation
or warranty, and without giving effect to any update to the Parent Disclosure
delivered by Parent to the Company prior to the Closing); (ii) any inaccuracy in
or breach of any representation or warranty made by Parent and Merger Sub in
Section 3 as if such representation and warranty had been made on and as of the
Closing Date (except for such representations and warranties that address
matters only as of a particular time, which need only be accurate as of such
time) (after having given effect to any updates to the Parent Disclosure
Schedule delivered to the Company prior to the Closing pursuant to Section
4.4(b), but without giving effect to any "Material Adverse Effect" or other
materiality qualification or any similar qualification contained or incorporated
directly in such representation or warranty); (iii) any breach of any covenant
or obligation of Parent or Merger Sub in this Agreement to be performed prior to
the Closing (including, without limitation, the covenants set forth in Sections
4 and 5); or (iv) any Legal Proceeding relating to any inaccuracy or breach of
the type referred to in clause "(i)," "(ii)" or "(iii)" above (including any
Legal Proceeding commenced by any Stockholder Indemnitee for the purpose of
enforcing any of its rights under this Section 9).

       9.3    DEDUCTIBLE. The Major Stockholders, on the one hand, and Parent,
on the other hand, shall not be required to make any indemnification payment
pursuant to Section 9.2(a) or Section 9.2(b), as the case may be, for any
inaccuracy in or breach of any of (a) the Company's representations and
warranties set forth in this Agreement (in the case of the Major Stockholders)
or (b) Parent and Merger Sub's representations and warranties in this Agreement
(in the case of Parent) until such time as the total amount of all Damages
(including, without limitation, the Damages arising from such inaccuracy or
breach and all other Damages arising from any other inaccuracies in or breaches
of any representations or warranties) that have been directly or indirectly
suffered or incurred by any one or more of the Parent Indemnitees or the
Stockholder Indemnitees, as the case may be, or to which any one or more of the
Parent Indemnitees or the Stockholder Indemnitees, as the case may be, has or
have otherwise become subject, exceeds $500,000 in the aggregate. If the total
amount of such Damages exceeds $500,000, then the Parent Indemnitees or the
Stockholder Indemnitees, as the case may be, shall be entitled to be indemnified
against and compensated and reimbursed only for the portion of such Damages that
exceeds $500,000. Notwithstanding the preceding sentence, no individual claim or
series of related claims for indemnification under this Section 9 may be
asserted unless it is (or they are) for an amount in excess of $15,000.

       9.4    EXCLUSIVE REMEDY FOR MONETARY DAMAGES.

              (a)    From and after the Closing, the total aggregate liability
of the Major Stockholders for Damages arising under Section 9.2(a) shall not
exceed the Escrow Fund. From and after the Closing, the total aggregate
liability of Parent for Damages arising under Section 9.2(b) shall not exceed a
cash amount equal to the aggregate value (as of the Closing Date) of the Parent
Capital Stock held in the Escrow Fund.

              (b)    Nothing in this Section 9.4 or elsewhere in this Agreement
shall affect the parties' rights to specific performance or other equitable
remedies with respect to the covenants referred to in this Agreement to be
performed after the Closing.


                                      55.
<PAGE>

              (c)    In the absence of fraud or intentional misconduct, from and
after the Closing, this Section 9 sets forth the exclusive remedy for monetary
Damages owing from the Indemnitors to the Indemnitees that arise from the
matters described in Section 9.2.

       9.5    NO CONTRIBUTION.

No stockholder of the Company shall have any right of contribution, right of
indemnity or other right or remedy against the Surviving Corporation in
connection with any indemnification obligation or any other liability to which
he may become subject under or in connection with this Agreement.

       9.6    INTEREST. If the Major Stockholders, on the one hand, or Parent,
on the other hand, are required to hold harmless, indemnify, compensate or
reimburse any Parent Indemnitee or Stockholder Indemnitee, as the case may be,
pursuant to this Section 9 with respect to any Damages, then the Major
Stockholders or Parent, as the case may be, shall also be liable to such Parent
Indemnitee or Stockholder Indemitee, as the case may be, for interest on the
amount of such Damages (for the period commencing as of the date on which such
the Major Stockholders or Parent, as the case may be, first received notice of a
claim for recovery by such Parent Indemnitee or Stockholder Indemnitee, as the
case may be, and ending on the date on which the liability of the Major
Stockholders or Parent, as the case may be, to is fully satisfied) at a floating
rate equal to the rate of interest publicly announced by Bank of America, N.T. &
S.A. from time to time as its prime, base or reference rate.

       9.7    DEFENSE OF THIRD PARTY CLAIMS. In the event of the assertion or
commencement by any Person of any claim or Legal Proceeding (whether against the
Surviving Corporation, against Parent or against any other Person) with respect
to which any of the Major Stockholders may become obligated to hold harmless,
indemnify, compensate or reimburse any Indemnitee pursuant to this Section 9,
Parent shall have the right, at its election, to proceed with the defense of
such claim or Legal Proceeding on its own. If Parent so proceeds with the
defense of any such claim or Legal Proceeding:

              (a)    all reasonable expenses relating to the defense of such
       claim or Legal Proceeding shall be borne and paid exclusively by the
       Major Stockholders;

              (b)    each Major Stockholder shall make available to Parent any
       documents and materials in his possession or control that may be
       necessary to the defense of such claim or Legal Proceeding; and

              (c)    Parent shall not have the right to settle, adjust or
       compromise such claim or Legal Proceeding with the consent of the
       Stockholders' Agent (as defined in Section 10.1); PROVIDED, HOWEVER, that
       such consent shall not be unreasonably withheld.

Parent shall give the Stockholders' Agent prompt notice of the commencement of
any such Legal Proceeding against Parent or the Surviving Corporation; PROVIDED,
HOWEVER, that any failure on the part of Parent to so notify the Stockholders'
Agent shall not limit any of the obligations of the Major Stockholder under this
Section 9 (except to the extent such failure materially prejudices the defense
of such Legal Proceeding).



                                      56.
<PAGE>

     9.8 EXERCISE OF REMEDIES BY PARENT INDEMNITEES OTHER THAN PARENT. No Parent
Indemnitee (other than Parent or any successor thereto or assign thereof) shall
be permitted to assert any indemnification claim or exercise any other remedy
under this Agreement unless Parent (or any successor thereto or assign thereof)
shall have consented to the assertion of such indemnification claim or the
exercise of such other remedy.

SECTION 10.  MISCELLANEOUS PROVISIONS

     10.1 STOCKHOLDERS' AGENTS. By virtue of their adoption of this Agreement
and approval of the transactions contemplated hereby, the stockholders of the
Company hereby irrevocably appoint Bill Newell and Fred Davenport as their joint
agents for purposes of Section 9 (the "Stockholders' Agents"), and Bill Newell
and Fred Davenport hereby accept their appointment as the Stockholders' Agents.
Parent shall be entitled to deal exclusively with the Stockholders' Agents on
all matters relating to Section 9, and shall be entitled to rely conclusively
(without further evidence of any kind whatsoever) on any document executed or
purported to be executed on behalf of any Merger Stockholder by both of the
Stockholders' Agents, and on any other action taken or purported to be taken on
behalf of any Merger Stockholder by the Stockholders' Agents, as fully binding
upon such stockholder. If one of the Stockholders' Agents shall die, become
disabled or otherwise be unable to fulfill his responsibilities as agent of the
Merger Stockholders, then the Merger Stockholders shall, within ten days after
such death or disability, appoint a successor agent and, promptly thereafter,
shall notify Parent of the identity of such successor. Any such successor shall
become a "Stockholders' Agents" for purposes of Section 9 and this Section 10.1.
If for any reason there is no Stockholders' Agent at any time, all references
herein to the Stockholders' Agents shall be deemed to refer to the Merger
Stockholders.

     10.2 FURTHER ASSURANCES. Each party hereto shall execute and cause to be
delivered to each other party hereto such instruments and other documents, and
shall take such other actions, as such other party may reasonably request (prior
to, at or after the Closing) for the purpose of carrying out or evidencing any
of the transactions contemplated by this Agreement.

     10.3 FEES AND EXPENSES. Subject to Section 9.2(a), each party to this
Agreement shall bear and pay all fees, costs and expenses (including legal fees,
costs and expenses and accounting fees, costs and expenses) that have been
incurred or that are incurred by such party in connection with the transactions
contemplated by this Agreement.

     10.4 ATTORNEYS' FEES. If any action or proceeding relating to this
Agreement or the enforcement of any provision of this Agreement is brought
against any party hereto, the prevailing party shall be entitled to recover
reasonable attorneys' fees, costs and disbursements (in addition to any other
relief to which the prevailing party may be entitled).

     10.5 NOTICES. Any notice or other communication required or permitted to be
delivered to any party under this Agreement shall be in writing and shall be
deemed properly delivered, given and received when delivered (by hand, by
registered mail, by courier or express delivery service or by facsimile) to the
address or facsimile telephone number set forth beneath the name


                                       57.
<PAGE>

of such party below (or to such other address or facsimile telephone number as
such party shall have specified in a written notice given to the other parties
hereto):

                  IF TO PARENT:

                  DNA Sciences, Inc.
                  2375 Garcia Avenue
                  Mountain View, CA 94043
                  Attention:
                  Phone: (650)
                  Fax: (650)

                  WITH A COPY TO:

                  Cooley Godward LLP
                  3000 El Camino Real
                  5 Palo Alto Square
                  Palo Alto, CA 94306
                  Attention: Robert L. Jones
                  Phone: (650) 843-5000
                  Fax: (650) 849-7400


                  IF TO THE COMPANY:

                  PPGx, Inc.
                  11099 North Torrey Pines Road
                  La Jolla, CA 92037
                  Attention:  Josh Baker
                  Phone: (919) 463-6702
                  Fax: (919) 379-6029


                  WITH A COPY TO:

                  Heller Ehrman White & McAuliffe LLP
                  4250 Executive Square, 7th Floor
                  La Jolla, CA 92037
                  Attention: Stephen C. Ferruolo
                  Phone:  (858) 450-8430
                  Fax:  (858) 450-8499


                  IF TO THE STOCKHOLDERS' AGENTS:

                  Fred Davenport
                  Pharmaceutical Product Development, Inc.


                                       58.
<PAGE>

                  3151 South 17th Street
                  Wilmington, NC 28412
                  Phone:  (910) 251-0081
                  Fax:  (910) 772-6951

                  Bill Newell
                  Axys Pharmaceuticals, Inc.
                  180 Kimball Way
                  South San Francisco, CA 94080
                  Phone:  (650) 829-1000
                  Fax:  (650) 829-1001


     10.6 CONFIDENTIALITY. Without limiting the generality of anything contained
in Section 5.6, on and at all times after the Closing Date, each party to this
Agreement shall keep confidential, and shall not use or disclose to any other
Person, any non-public document or other non-public information in such
stockholder's possession that relates to the business of the Company or Parent.

     10.7 TIME OF THE ESSENCE. Time is of the essence of this Agreement.

     10.8 HEADINGS. The underlined headings contained in this Agreement are for
convenience of reference only, shall not be deemed to be a part of this
Agreement and shall not be referred to in connection with the construction or
interpretation of this Agreement.

     10.9 COUNTERPARTS. This Agreement may be executed in several counterparts,
each of which shall constitute an original and all of which, when taken
together, shall constitute one agreement.

     10.10 GOVERNING LAW. This Agreement shall be construed in accordance with,
and governed in all respects by, the internal laws of the State of Delaware
(without giving effect to principles of conflicts of laws).

     10.11 SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon the
Company and its successors and assigns (if any), Parent and its successors and
assigns (if any), and Merger Sub and its successors and assigns (if any). This
Agreement shall inure to the benefit of: the Company, the Company's stockholders
(to the extent set forth in Section 1.5) and the Stockholder Indemnitees (to the
extent set forth in Section 9), the holders of assumed Company Options (to the
extent set forth in Section 1.6), Parent, Merger Sub, the other Parent
Indemnitees (subject to Section 9.6), and the respective successors and assigns
(if any) of the foregoing. Parent may freely assign any or all of its rights
under Section 9, in whole or in part, to any other Person without obtaining the
consent or approval of any other party hereto or of any other Person.

     10.12 REMEDIES CUMULATIVE; SPECIFIC PERFORMANCE. The rights and remedies of
the parties hereto shall be cumulative (and not alternative). The parties to
this Agreement agree that, in the event of any breach or threatened breach by
any party to this Agreement of any covenant,


                                       59.
<PAGE>

obligation or other provision set forth in this Agreement for the benefit of any
other party to this Agreement, such other party shall be entitled (in addition
to any other remedy that may be available to it) to (a) a decree or order of
specific performance or mandamus to enforce the observance and performance of
such covenant, obligation or other provision, and (b) an injunction restraining
such breach or threatened breach.

     10.13 WAIVER.

          (a) No failure on the part of any Person to exercise any power, right,
privilege or remedy under this Agreement, and no delay on the part of any Person
in exercising any power, right, privilege or remedy under this Agreement, shall
operate as a waiver of such power, right, privilege or remedy; and no single or
partial exercise of any such power, right, privilege or remedy shall preclude
any other or further exercise thereof or of any other power, right, privilege or
remedy.

          (b) No Person shall be deemed to have waived any claim arising out of
this Agreement, or any power, right, privilege or remedy under this Agreement,
unless the waiver of such claim, power, right, privilege or remedy is expressly
set forth in a written instrument duly executed and delivered on behalf of such
Person; and any such waiver shall not be applicable or have any effect except in
the specific instance in which it is given.

     10.14 AMENDMENTS. This Agreement may not be amended, modified, altered or
supplemented other than by means of a written instrument duly executed and
delivered on behalf of all of the parties hereto.

     10.15 SEVERABILITY. In the event that any provision of this Agreement, or
the application of any such provision to any Person or set of circumstances,
shall be determined to be invalid, unlawful, void or unenforceable to any
extent, the remainder of this Agreement, and the application of such provision
to Persons or circumstances other than those as to which it is determined to be
invalid, unlawful, void or unenforceable, shall not be impaired or otherwise
affected and shall continue to be valid and enforceable to the fullest extent
permitted by law.

     10.16 PARTIES IN INTEREST. Except for the provisions of Sections 1.5, 1.6
and 9, none of the provisions of this Agreement is intended to provide any
rights or remedies to any Person other than the parties hereto and their
respective successors and assigns (if any).

     10.17 ENTIRE AGREEMENT. This Agreement and the other agreements referred to
herein set forth the entire understanding of the parties hereto relating to the
subject matter hereof and thereof and supersede all prior agreements and
understandings among or between any of the parties relating to the subject
matter hereof and thereof; PROVIDED, HOWEVER, that the Confidentiality and
Non-Disclosure Agreement executed on behalf of Parent and the Company on
September 6, 2000 shall not be superseded by this Agreement and shall remain in
effect in accordance with its terms until the earlier of (a) the Effective Time,
or (b) the date on which such Confidentiality and Nondisclosure Agreement is
terminated in accordance with its terms.

     10.18 CONSTRUCTION.

                                       60.
<PAGE>

          (a) For purposes of this Agreement, whenever the context requires: the
singular number shall include the plural, and vice versa; the masculine gender
shall include the feminine and neuter genders; the feminine gender shall include
the masculine and neuter genders; and the neuter gender shall include the
masculine and feminine genders.

          (b) The parties hereto agree that any rule of construction to the
effect that ambiguities are to be resolved against the drafting party shall not
be applied in the construction or interpretation of this Agreement.

          (c) As used in this Agreement, the words "include" and "including,"
and variations thereof, shall not be deemed to be terms of limitation, but
rather shall be deemed to be followed by the words "without limitation."

          (d) Except as otherwise indicated, all references in this Agreement to
"Sections" and "Exhibits" are intended to refer to Sections of this Agreement
and Exhibits to this Agreement.




                                       61.
<PAGE>

         The parties hereto have caused this Agreement to be executed and
delivered as of December 17, 2000.

                                 DNA SCIENCES, INC.,
                                  a Delaware corporation

                                 By: /s/ Steven Lehrer
                                    --------------------------------------------
                                    Chief Business Officer,
                                    DNA Sciences, Inc.



                                 PIPO ACQUISITION CORP.,
                                  a Delaware corporation

                                 By: /s/ Steven Lehrer
                                    --------------------------------------------
                                    President and Chief Executive Officer,
                                    PIPO Acquisition Corp.



                                 PPGX, INC.,
                                  a Delaware corporation

                                 By: /s/ Joshua S. Baker
                                    --------------------------------------------
                                    President,
                                    PPGx, Inc.





                                       62.
<PAGE>

                                    EXHIBIT A

                               CERTAIN DEFINITIONS

         For purposes of the Agreement (including this Exhibit A):

         ACQUIRED CORPORATION CONTRACT. "Acquired Corporation Contract" shall
mean any contract: (a) to which any of the Acquired Corporations is a party; (b)
by which any of the Acquired Corporations or any asset of any of the Acquired
Corporations is or may become bound or under which any of the Acquired
Corporations has, or may become subject to, any obligation; or (c) under which
any of the Acquired Corporations has or may acquire any right or interest.

         ACQUIRED CORPORATION PROPRIETARY ASSET. "Acquired Corporation
Proprietary Asset" shall mean any Proprietary Asset owned by or licensed to any
of the Acquired Corporations or otherwise used by any of the Acquired
Corporations.

         ACQUISITION TRANSACTION. "Acquisition Transaction" shall mean any
transaction involving:

              (a) the sale, license, disposition or acquisition of all or a
         material portion of the any of the Acquired Corporations' business or
         assets;

              (b) the issuance, disposition or acquisition of (i) any capital
         stock or other equity security of any of the Acquired Corporations'
         (other than common stock issued to employees of the Acquired
         Corporations, upon exercise of Company Options or otherwise, in
         routine transactions in accordance with the Acquired Corporations'
         past practices), (ii) any option, call or right (whether or not
         immediately exercisable) to acquire any capital stock or other equity
         security of the any of the Acquired Corporations (other than stock
         options granted to employees of the Acquired Corporations in routine
         transactions in accordance with the Acquired Corporations' past
         practices), or (iii) any security, instrument or obligation that is or
         may become convertible into or exchangeable for any capital stock or
         other equity security of any of the Acquired Corporations; or

              (c) any merger, consolidation, business combination,
         reorganization or similar transaction involving any of the Acquired
         Corporations.

         AGREEMENT. "Agreement" shall mean the Agreement and Plan of Merger and
Reorganization to which this Exhibit A is attached (including the Company
Disclosure Schedule and the Parent Disclosure Schedule), as it may be amended
from time to time.

         COMPANY CAPITAL STOCK. "Company Capital Stock" shall mean,
collectively, the Company Common Stock and the Company Series A Preferred Stock.

         COMPANY DISCLOSURE SCHEDULE. "Company Disclosure Schedule" shall mean
the schedule (dated as of the date of the Agreement) delivered to Parent on
behalf of the Company.

         CONSENT. "Consent" shall mean any approval, consent, ratification,
permission,  waiver or authorization (including any Governmental Authorization).


                                       1.
<PAGE>

         CONTRACT. "Contract" shall mean any written, oral or other agreement,
contract, subcontract, lease, understanding, instrument, note, warranty,
insurance policy, benefit plan or legally binding commitment or undertaking of
any nature.

         DAMAGES. "Damages" shall include any loss, damage, injury, decline in
value, lost opportunity, liability, claim, demand, settlement, judgment, award,
fine, penalty, Tax, fee (including reasonable attorneys' fees), charge, cost
(including costs of investigation) or expense of any nature.

         ENCUMBRANCE. "Encumbrance" shall mean any lien, pledge, hypothecation,
charge, mortgage, security interest, encumbrance, claim, infringement,
interference, option, right of first refusal, preemptive right, community
property interest or restriction of any nature (including any restriction on the
voting of any security, any restriction on the transfer of any security or other
asset, any restriction on the receipt of any income derived from any asset, any
restriction on the use of any asset and any restriction on the possession,
exercise or transfer of any other attribute of ownership of any asset).

         ENTITY. "Entity" shall mean any corporation (including any non-profit
corporation), general partnership, limited partnership, limited liability
partnership, joint venture, estate, trust, company (including any limited
liability company or joint stock company), firm or other enterprise,
association, organization or entity.

         EXCESS TRANSACTION EXPENSES. "Excess Transaction Expenses" shall mean
(A) 50% of the first $400,000 in aggregate fees, costs and expenses payable by
the Company to the Company's legal counsel, accountants and other advisors
(other than P(2) Partners (the "Company Financial Advisor") and incurred in
connection with the transactions contemplated by this Agreement, PLUS (B) 100%
of the aggregate fees, costs and expenses payable to the Company's legal
counsel, accountants and other advisors (other than the Company Financial
Advisor) in excess of $400,000 and incurred in connection with the transactions
contemplated by this Agreement, PLUS (C) all fees, costs and expenses payable by
the Company to the Company Financial Advisor and incurred in connection with the
transactions contemplated by this Agreement.

         GOVERNMENTAL AUTHORIZATION. "Governmental Authorization" shall mean
any: (a) permit, license, certificate, franchise, permission, clearance,
registration, qualification or authorization issued, granted, given or otherwise
made available by or under the authority of any Governmental Body or pursuant to
any Legal Requirement; or (b) right under any Contract with any Governmental
Body.

         GOVERNMENTAL BODY. "Governmental Body" shall mean any: (a) nation,
state, commonwealth, province, territory, county, municipality, district or
other jurisdiction of any nature; (b) federal, state, local, municipal, foreign
or other government; or (c) governmental or quasi-governmental authority or
component of any nature (including any governmental branch, division,
department, agency, commission, instrumentality, official, organization, unit,
body or Entity and any court or other tribunal).

         INDEMNITEES.  "Indemnitees" shall mean the Parent Indemnitees and the
Stockholder Indemnitees.


                                       2.
<PAGE>

         KNOWLEDGE. Information shall be deemed "known to" or "to the Knowledge"
of the Company if that information is actually known by any of Josh Baker or
Jeff Hall or should be known to such individual after reasonable inquiry by such
individual. Information shall be deemed "known to" or "to the Knowledge" of
Parent if that information is actually known by any officer or director of
Parent or should be known to such officer or director after reasonable inquiry
by such officer or director.

         LEGAL PROCEEDING. "Legal Proceeding" shall mean any action, suit,
litigation, arbitration, proceeding (including any civil, criminal,
administrative, investigative or appellate proceeding), hearing, inquiry, audit,
examination or investigation commenced, brought, conducted or heard by or
before, or otherwise involving, any court or other Governmental Body or any
arbitrator or arbitration panel.

         LEGAL REQUIREMENT. "Legal Requirement" shall mean any federal, state,
local, municipal, foreign or other law, statute, constitution, principle of
common law, resolution, ordinance, code, edict, decree, rule, regulation,
publicly available administrative interpretation, ruling or requirement issued,
enacted, adopted, promulgated, implemented or otherwise put into effect by or
under the authority of any Governmental Body.

         MATERIAL ADVERSE EFFECT. A "Material Adverse Effect" on the Acquired
Corporations means any change, effect, event, occurrence, state of facts or
development that is materially adverse to the business, condition, assets,
liabilities, operations or financial performance of one or more of the Acquired
Corporations. A "Material Adverse Effect" on Parent means any change, effect,
event, occurrence, state of facts or development that is materially adverse to
the business, condition, assets, liabilities, operations or financial
performance of Parent; PROVIDED, HOWEVER, that any adverse change, effect,
event, occurrence, state of facts or development affecting Parent's ability to
obtain or arrange public or private debt or equity financing on terms acceptable
to Parent or otherwise adversely affecting the financial markets in general or
the financial markets for the industry sector in which Parent competes shall not
be deemed to constitute, nor taken into account in determining whether there has
been, a Material Adverse Effect on Parent; PROVIDED FURTHER HOWEVER, that any
adverse change, effect, event, occurrence, state of facts or development
referred to in the preceding proviso will be taken into account in determining
whether there has been a Material Adverse Effect on Parent (but will not in and
of itself constitute a Material Adverse Effect on Parent) if such adverse
change, effect, event, occurrence, state of facts or development resulted from
the gross negligence or willful misconduct of Parent or its Representatives and
such adverse change, effect, event, occurrence, state of facts or development
has resulted in an obligation of Parent to pay money damages in an amount in
excess of $300,000.

         PARENT DISCLOSURE SCHEDULE. "Parent Disclosure Schedule" shall mean the
schedule (dated as of the date of the Agreement) delivered to the Company on
behalf of Parent and Merger Sub.

         PARENT INDEMNITEES. "Parent Indemnitees" shall mean the following
Persons: (a) Parent; (b) Parent's current and future affiliates (including the
Surviving Corporation); (c) the respective Representatives of the Persons
referred to in clauses "(a)" and "(b)" above; and (d) the respective successors
and assigns of the Persons referred to in clauses "(a)", "(b)" and "(c)"


                                       3.
<PAGE>

above; PROVIDED, HOWEVER, that the stockholders of the Company shall not be
deemed to be "Parent Indemnitees."

         PARENT PREFERRED STOCK. "Parent Preferred Stock" shall mean
collectively, the Series A Preferred Stock ($0.001 par value per share) of
Parent, the Series B Preferred Stock ($0.001 par value per share) of Parent, the
Parent Series C Preferred Stock and the Parent Series D Preferred Stock.

         PARENT SERIES C PREFERRED STOCK. "Parent Series C Preferred Stock"
shall mean the Series C Preferred Stock (0.001 par value per share) of Parent.

         PERMITTED ENCUMBRANCE. "Permitted Encumbrance" shall mean any (i) any
Encumbrance for Taxes (other than income taxes) either not yet due and payable
or being contested in good faith by appropriate proceedings and for which
adequate reserves have been established on the Acquired Corporation Financial
Statements in accordance with generally accepted accounting principles applied
on a consistent basis throughout the periods covered and (ii) mechanic's,
materialmen's, workmen's, warehousemen's and other similar liens incurred in the
ordinary course of business with respect to obligations that are not past due or
that are being contested in good faith by appropriate proceedings and for which
adequate reserves have been established on the Acquired Corporation Financial
Statements in accordance with generally accepted accounting principles applied
on a consistent basis throughout the periods covered.

         PERSON. "Person" shall mean any individual, Entity or Governmental
Body.

         PROPRIETARY ASSET. "Proprietary Asset" shall mean any: (a) patent,
patent application, trademark (whether registered or unregistered), trademark
application, trade name, fictitious business name, service mark (whether
registered or unregistered), service mark application, copyright (whether
registered or unregistered), copyright application, maskwork, maskwork
application, trade secret, know-how, customer list, franchise, system, computer
software, computer program, source code, algorithm, invention, design,
proprietary product, technology, proprietary right or other intellectual
property right or intangible asset; or (b) right to use or exploit any of the
foregoing.

         REPRESENTATIVES. "Representatives" shall mean officers, directors,
employees, agents, attorneys, accountants, advisors and representatives.

         SUBSIDIARY. An entity shall be deemed to be a "Subsidiary" of another
Person if such Person directly or indirectly owns, beneficially or of record,
(a) an amount of voting securities of other interests in such Entity that is
sufficient to enable such Person to elect at least a majority of the members of
such Entity's board of directors or other governing body, or (b) at least 50% of
the outstanding equity or financial interests or such Entity.

         STOCKHOLDER INDEMNITEES. "Stockholder Indemnitees" shall mean the
following Persons: (a) the Merger Stockholders; (b) the Merger Stockholders'
current and future affiliates; (c) the respective Representatives of the Persons
referred to in clauses "(a)" and "(b)" above; and (d) the respective successors
and assigns of the Persons referred to in clauses "(a)", "(b)" and "(c)" above;
PROVIDED, HOWEVER, that the Company shall not be deemed to be a "Stockholder
Indemnitee."

                                       4.
<PAGE>

         TAX. "Tax" shall mean any tax (including any income tax, franchise tax,
capital gains tax, gross receipts tax, value-added tax, surtax, excise tax, ad
valorem tax, transfer tax, stamp tax, sales tax, use tax, property tax, business
tax, withholding tax or payroll tax), levy, assessment, tariff, duty (including
any customs duty), deficiency or fee, and any related charge or amount
(including any fine, penalty or interest), imposed, assessed or collected by or
under the authority of any Governmental Body.

         TAX RETURN. "Tax Return" shall mean any return (including any
information return), report, statement, declaration, estimate, schedule, notice,
notification, form, election, certificate or other document or information filed
with or submitted to, or required to be filed with or submitted to, any
Governmental Body in connection with the determination, assessment, collection
or payment of any Tax or in connection with the administration, implementation
or enforcement of or compliance with any Legal Requirement relating to any Tax.




                                       5.
<PAGE>

                                    EXHIBITS

Exhibit A     -    Certain definitions

Exhibit B     -    Form of Voting Agreement

Exhibit C     -    Form of Escrow Agreement

Exhibit D     -    Form of Amended and Restated Certificate

Exhibit E     -    Forms of tax representation letters

Exhibit F     -    Form of Noncompetition Agreement

Exhibit G     -    Persons to Execute Offer Letters

Exhibit H     -    Form of Offer Letter

Exhibit I     -    Form of Release

Exhibit J     -    Form of Underwriter Lockup Agreement

Exhibit K     -    Form of Amended and Restated Distributor Agreement

Exhibit L     -    Form of Amended and Restated Technology Transfer Agreement

Exhibit M     -    Form of PPD Clarification Letter

Exhibit N     -    Form of PPD Real Property Indemnity Letter

Exhibit O     -    Form of Axys Covenant Not to Sue

Exhibit P     -    Form of Axys Assignment Letter

Exhibit Q     -    Form of Amended and Restated Investor Rights Agreement

Exhibit R     -    Form of Amended and Restated Co-Sale Agreement

Exhibit S     -    Form of legal opinion of Heller Ehrman White & McAuliffe LLP

Exhibit T     -    Form of legal opinion of Cooley Godward LLP





                                       1.

<PAGE>

                               AMENDMENT NO. 1 TO
                               AGREEMENT AND PLAN
                          OF MERGER AND REORGANIZATION

     THIS AMENDMENT NO. 1 TO AGREEMENT AND PLAN OF MERGER AND REORGANIZATION
(this "Amendment") is made and entered into as of December 22, 2000, by and
among: DNA SCIENCES, INC., a Delaware corporation ("Parent"), PIPO ACQUISITION
CORP., a Delaware corporation and a wholly owned subsidiary of Parent ("Merger
Sub"), and PPGX, INC., a Delaware corporation (the "Company"). Certain
capitalized terms not otherwise defined herein are defined in the Reorganization
Agreement (as defined below).

                                    RECITALS

     A.  Parent, Merger Sub and the Company intend to effect a merger of Merger
Sub into the Company in accordance with that certain Agreement and Plan of
Merger and Reorganization dated December 17, 2000, among Parent, Merger Sub and
the Company (the "Reorganization Agreement").

     B.  Parent, Merger Sub and the Company desire to amend the Reorganization
Agreement as set forth in this Amendment.

                                    AGREEMENT

     The parties to this Amendment, intending to be legally bound, agree as
follows:

1. DEFINITION OF "AGGREGATE PARENT COMMON NUMBER."

     Section 1.5(b)(vii)(7) is amended by replacing "Initial Series C Closing
Date" with "date hereof."

2. DEFINITION OF "DOWN ROUND STOCK."

     Section 1.5(b)(ix) is amended by replacing "$14.27" with "$14.37."

3. SECTION 1.5(d) AND SECTION 1.8(c).

     Section 1.5(d) and Section 1.8(c) is amended by replacing "$14.27" with
"$14.37."

4. SECTION 1.6.

     Clauses "(ii)" and "(iii)" of Section 1.6 are amended by replacing
"Exchange Ratio" with "Remainder Exchange Ratio."

5. SECTION 3.23.

     Section 3.23 is amended and restated to read in its entirety, "Reserved."

6. SECTION 4.5(d).


                                      1.
<PAGE>

     Section 4.5(d) is amended and restated to read in its entirety, "Reserved."

7. SECTION 7.8.

     Section 7.8 is amended and restated to read in its entirety, "Reserved."

8. REMAINING TERMS.

     All other provisions of the Reorganization Agreement remain in full force
and effect and unmodified by this Amendment.

9. GOVERNING LAW.

     This Amendment shall be governed by and construed in accordance with the
internal laws of the State of Delaware, without reference to principles of
conflicts of law.



                                      2.
<PAGE>



     The parties hereto have caused this Amendment to be executed and delivered
as of December 22, 2000.


                                  DNA SCIENCES, INC.,
                                    a Delaware corporation

                                  By: /s/ Steven Lehrer
                                      ---------------------------------------
                                      Chief Business Officer,
                                      DNA Sciences, Inc.



                                  PIPO ACQUISITION CORP.,
                                    a Delaware corporation

                                  By: /s/ Steven Lehrer
                                      ---------------------------------------
                                      President and Chief Executive Officer,
                                      PIPO Acquisition Corp.


                                  PPGX, INC.,
                                    a Delaware corporation

                                  By: /s/ Joshua S. Baker
                                      ---------------------------------------
                                      President,
                                      PPGx, Inc.




                                      3.