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                                                                    EXHIBIT 10.4

                               DNA SCIENCES, INC.

                 2001 NON-EMPLOYEE DIRECTORS' STOCK OPTION PLAN

                ADOPTED BY THE BOARD OF DIRECTORS JANUARY 3, 2001
                 APPROVED BY STOCKHOLDERS _____________ ___, 2001
             EFFECTIVE DATE: CLOSING DATE OF INITIAL PUBLIC OFFERING
                             TERMINATION DATE: NONE

1.         PURPOSES.

           (a)       ELIGIBLE OPTION RECIPIENTS. The persons eligible to
receive Options are the Non-Employee Directors of the Company.

           (b)       AVAILABLE OPTIONS. The purpose of the Plan is to
provide a means by which Non-Employee Directors may be given an
opportunity to benefit from increases in value of the Common Stock through
the granting of Nonstatutory Stock Options.

           (c)       GENERAL PURPOSE. The Company, by means of the Plan,
seeks to retain the services of its Non-Employee Directors, to secure and
retain the services of new Non-Employee Directors and to provide incentives
for such persons to exert maximum efforts for the success of the Company and
its Affiliates.

2.         DEFINITIONS.

           (a)       "AFFILIATE" means any parent corporation or subsidiary
corporation of the Company, whether now or hereafter existing, as those terms
are defined in Sections 424(e) and (f), respectively, of the Code.

           (b)       "ANNUAL GRANT" means an Option granted annually to all
Non-Employee Directors who meet the criteria specified in subsection 6(b) of
the Plan.

           (c)       "ANNUAL MEETING" means the annual meeting of the
stockholders of the Company.

           (d)       "BOARD" means the Board of Directors of the Company.

           (e)       "CODE" means the Internal Revenue Code of 1986, as
amended.

           (f)       "COMMITTEE" means a committee of one or more members of
the Board appointed by the Board in accordance with subsection 3(c).

           (g)       "COMMON STOCK" means the common stock of the Company.

           (h)       "COMPANY" means DNA Sciences, Inc., a Delaware
corporation.

           (i)       "CONSULTANT" means any person, including an advisor, (i)
engaged by the Company or an Affiliate to render consulting or advisory
services and who is compensated for

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such services or (ii) who is a member of the Board of Directors of an
Affiliate. However, the term "Consultant" shall not include either Directors
of the Company who are not compensated by the Company for their services as
Directors or Directors of the Company who are merely paid a director's fee by
the Company for their services as Directors.

           (j)       "CONTINUOUS SERVICE" means that the Optionholder's
service with the Company or an Affiliate, whether as an Employee, Director or
Consultant, is not interrupted or terminated. The Optionholder's Continuous
Service shall not be deemed to have terminated merely because of a change in
the capacity in which the Optionholder renders service to the Company or an
Affiliate as an Employee, Consultant or Director or a change in the entity
for which the Optionholder renders such service, provided that there is no
interruption or termination of the Optionholder's service. For example, a
change in status without interruption from a Non-Employee Director of the
Company to a Consultant of an Affiliate or an Employee of the Company will
not constitute an interruption of Continuous Service. The Board or the chief
executive officer of the Company, in that party's sole discretion, may
determine whether Continuous Service shall be considered interrupted in the
case of any leave of absence approved by that party, including sick leave,
military leave or any other personal leave.

           (k)       "DIRECTOR" means a member of the Board of Directors of
the Company.

           (l)       "DISABILITY" means the inability of a person, in the
opinion of a qualified physician acceptable to the Company, to perform the
major duties of that person's position with the Company or an Affiliate of
the Company because of the sickness or injury of the person.

           (m)       "EMPLOYEE" means any person employed by the Company or
an Affiliate. Mere service as a Director or payment of a director's fee by
the Company or an Affiliate shall not be sufficient to constitute
"employment" by the Company or an Affiliate.

           (n)       "EXCHANGE ACT" means the Securities Exchange Act of
1934, as amended.

           (o)       "FAIR MARKET VALUE" means, as of any date, the value of
the Common Stock determined as follows:

                     (i)       If the Common Stock is listed on any
established  stock exchange or traded on the Nasdaq National Market or the
Nasdaq SmallCap Market, the Fair Market Value of a share of Common Stock
shall be the closing sales price for such stock (or the closing bid, if no
sales were reported) as quoted on such exchange or market (or the exchange or
market with the greatest volume of trading in the Common Stock) on the last
market trading day prior to the day of determination, THE WALL STREET JOURNAL
or such other source as the Board deems reliable.

                     (ii)      In the absence of such markets for the Common
Stock,  the Fair Market Value shall be determined in good faith by the Board.

           (p)       "INITIAL GRANT" means an Option granted to a
Non-Employee Director who meets the criteria specified in subsection 6(a) of
the Plan.

           (q)       "IPO DATE" means the closing date of the initial
public offering of the Common Stock.

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           (r)       "NON-EMPLOYEE DIRECTOR" means a Director who is not an
Employee.

           (s)       "NONSTATUTORY STOCK OPTION" means an Option not intended
to qualify as an incentive stock option within the meaning of Section 422 of
the Code and the regulations promulgated thereunder.

           (t)       "OFFICER" means a person who is an officer of the
Company within the meaning of Section 16 of the Exchange Act and the rules
and regulations promulgated thereunder.

           (u)       "OPTION" means a Nonstatutory Stock Option granted
pursuant to the Plan.

           (v)       "OPTION AGREEMENT" means a written agreement between the
Company and an Optionholder evidencing the terms and conditions of an
individual Option grant. Each Option Agreement shall be subject to the terms
and conditions of the Plan.

           (w)       "OPTIONHOLDER" means a person to whom an Option is
granted pursuant to the Plan or, if applicable, such other person who holds
an outstanding Option.

           (x)       "PLAN" means this DNA Sciences, Inc. 2001 Non-Employee
Directors' Stock Option Plan.

           (y)       "RULE 16b-3" means Rule 16b-3 promulgated under the
Exchange Act or any successor to Rule 16b-3, as in effect from time to time.

           (z)       "SECURITIES ACT" means the Securities Act of 1933, as
amended.

3.         ADMINISTRATION.

           (a)       ADMINISTRATION BY BOARD. The Board shall administer the
Plan. The Board may delegate administration of the Plan to a committee, as
provided in subsection 3(c).

           (b)       POWERS OF BOARD. The Board shall have the power,
subject to, and within the limitations of, the express provisions of the
Plan:

                     (i)       To determine the provisions of each Option to
the extent not specified in the Plan.

                     (ii)      To construe and interpret the Plan and
Options  granted  under it, and to establish, amend and revoke rules and
regulations for its administration. The Board, in the exercise of this power,
may correct any defect, omission or inconsistency in the Plan or in any
Option Agreement, in a manner and to the extent it shall deem necessary or
expedient to make the Plan fully effective.

                     (iii)     To amend the Plan or an Option as provided in
Section 12.

                     (iv)      To terminate or suspend the Plan as provided
in Section 13.

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                     (v)       Generally, to exercise such powers and to
perform  such acts as the Board deems necessary or expedient to promote
the best interests of the Company that are not in conflict with the
provisions of the Plan.

           (c)       DELEGATION TO COMMITTEE. The Board may delegate
administration of the Plan to a Committee or Committees of one or more
members of the Board, and the term "Committee" shall apply to any person or
persons to whom such authority has been delegated. If administration is
delegated to a Committee, the Committee shall have, in connection with the
administration of the Plan, the powers theretofore possessed by the Board,
including to power to delegate to a subcommittee any of the administrative
power the Committee is authorized to exercise (and references in this Plan to
the Board shall thereafter be to the Committee or subcommittee), subject,
however, to such resolutions, not inconsistent with the provisions of the
Plan, as may be adopted from time to time by the Board. The Board may abolish
the committee at any time and revest in the Board the administration of the
Plan.

           (d)       EFFECT OF BOARD'S DECISION. All determinations,
interpretations and constructions made by the Board in good faith shall not
be subject to review by any person and shall be final, binding and conclusive
on all persons.

4.         SHARES SUBJECT TO THE PLAN.

           (a)       SHARE RESERVE. Subject to the provisions of Section 11
relating to adjustments upon changes in stock, the Common Stock that may be
issued pursuant to Options shall not exceed three hundred forty thousand
(340,000) shares of Common Stock.

           (b)       REVERSION OF SHARES TO THE SHARE RESERVE. If any Option
shall for any reason expire or otherwise terminate, in whole or in part,
without having been exercised in full, the shares of Common Stock not
acquired under such Option shall revert to and again become available for
issuance under the Plan.

           (c)       SOURCE OF  SHARES. The shares of Common Stock subject
to the Plan may be  unissued  shares or reacquired shares, bought on the
market or otherwise.

5.         ELIGIBILITY.

           Options automatically shall be granted under the Plan to all
Non-Employee Directors as set forth in Section 6 of the Plan. Notwithstanding
the foregoing, no Options shall be granted under the Plan to any Non-Employee
Director who is a representative of a stockholder or stockholders of the
Company and who in such capacity and/or by virtue of any agreement with or
policy of such stockholder or stockholders is unable to receive an Option.

6.         NON-DISCRETIONARY GRANTS.

           (a)       INITIAL GRANTS. Without any further action of the Board,
each person who is elected or appointed for the first time to be a
Non-Employee Director after the IPO Date automatically shall upon the date of
his or her initial election or appointment by the Board or stockholders of
the Company be granted an Initial Grant to purchase sixteen thousand (16,000)
shares of Common Stock on the terms and conditions set forth herein.

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           (b)       ANNUAL GRANTS. Without any further action of the Board,
a Non-Employee Director shall be granted an Annual Grant as follows. On the
day following each Annual Meeting, commencing with the Annual Meeting in
2002, each person who is then a Non-Employee Director automatically shall be
granted an Annual Grant to purchase four thousand (4,000) shares of Common
Stock on the terms and conditions set forth herein.

7.         OPTION PROVISIONS.

           Each Option shall be in such form and shall contain such terms and
conditions as required by the Plan. Each Option shall contain such additional
terms and conditions, not inconsistent with the Plan, as the Board shall deem
appropriate. Each Option shall include (through incorporation of provisions
hereof by reference in the Option or otherwise) the substance of each of the
following provisions:

           (a)       TERM. No Option shall be exercisable after the
expiration of ten (10) years from the date it was granted.

           (b)       EXERCISE PRICE. The exercise price of each Option shall
be one hundred percent (100%) of the Fair Market Value of the stock subject
to the Option on the date the Option is granted. Notwithstanding the
foregoing, an Option may be granted with an exercise price lower than that
set forth in the preceding sentence if such Option is granted pursuant to an
assumption or substitution for another option in a manner satisfying the
provisions of Section 424(a) of the Code.

           (c)       CONSIDERATION. The purchase price of stock acquired
pursuant to an Option may be paid, to the extent permitted by applicable
statutes and regulations, in any combination of the following methods:

                     (i)       By cash or check.

                     (ii)      Provided that at the time of exercise the
Common Stock is publicly traded and quoted regularly by delivery of
already-owned shares of Common Stock either that the Optionholder has held
for the period required to avoid a charge to the Company's reported earnings
(generally six months) or that the Optionholder did not acquire, directly or
indirectly from the Company, that are owned free and clear of any liens,
claims, encumbrances or security interests, and that are valued at Fair
Market Value on the date of exercise. "Delivery" for these purposes shall
include delivery to the Company of the Optionholder's attestation of
ownership of such shares of Common Stock in a form approved by the Company.
Notwithstanding the foregoing, the Optionholder may not exercise the Option
by tender to the Company of Common Stock to the extent such tender would
violate the provisions of any law, regulation or agreement restricting the
redemption of the Company's stock.

                     (iii)     Provided that at the time of exercise the
Common Stock is publicly traded and quoted regularly pursuant to a program
developed under Regulation T (or similar rule or regulation) as promulgated
by the Federal Reserve Board that, prior to the issuance of Common Stock,
results in either the receipt of cash (or check) by the Company or the
receipt of irrevocable instructions to pay the aggregate exercise price to
the Company from the sales proceeds.

                                  5.

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           (d)       TRANSFERABILITY. An Option shall be transferable to the
extent provided in the Option Agreement. If the Option Agreement does not
provide for transferability, then the Option shall not be transferable except
by will or by the laws of descent and distribution and shall be exercisable
during the lifetime of the Optionholder only by the Optionholder.
Notwithstanding the foregoing, the Optionholder may, by delivering written
notice to the Company, in a form satisfactory to the Company, designate a
third party who, in the event of the death of the Optionholder, shall
thereafter be entitled to exercise the Option.

           (e)       EXERCISE SCHEDULE. The Option shall be exercisable as
the shares of Common Stock subject to the Option vest.

           (f)       VESTING SCHEDULE. Options shall vest as follows:

                     (i)       An Initial Grant shall vest in four (4) equal
annual  installments  at a rate of one-fourth (1/4) of the total shares
subject to such Option. Each installment shall vest on each of the first,
second, third, and fourth anniversary of the date of grant; PROVIDED,
HOWEVER, that vesting shall cease on termination of the Optionholder's
Continuous Service.

                     (ii)      An Annual Grant shall vest in two (2) equal
installments  at a rate of one-half (1/2) of the total number of shares
subject to such Option. The first installment shall vest six (6) months from
the date of grant of such Option and the second installment shall vest on the
first anniversary of the date of grant; PROVIDED, HOWEVER, that vesting shall
cease on termination of the Optionholder's Continuous Service.

           (g)       TERMINATION OF CONTINUOUS SERVICE. In the event an
Optionholder's Continuous Service terminates (other than upon the
Optionholder's death or Disability), the Optionholder may exercise his or her
Option (to the extent that the Optionholder was entitled to exercise it as of
the date of termination) but only within such period of time ending on the
earlier of (i) the date three (3) months following the termination of the
Optionholder's Continuous Service, or (ii) the expiration of the term of the
Option as set forth in the Option Agreement. If, after termination, the
Optionholder does not exercise his or her Option within the time specified in
the Option Agreement, the Option shall terminate.

           (h)       EXTENSION OF TERMINATION DATE. If the exercise of the
Option following the termination of the Optionholder's Continuous Service
(other than upon the Optionholder's death or Disability) would be prohibited
at any time solely because the issuance of shares would violate the
registration requirements under the Securities Act, then the Option shall
terminate on the earlier of (i) the expiration of the term of the Option set
forth in subsection 7(a) or (ii) the expiration of a period of three (3)
months after the termination of the Optionholder's Continuous Service during
which the exercise of the Option would not be in violation of such
registration requirements.

           (i)       DISABILITY OF OPTIONHOLDER. In the event an
Optionholder's Continuous Service terminates as a result of the
Optionholder's Disability, the Optionholder may exercise his or her Option
(to the extent that the Optionholder was entitled to exercise it as of the
date of termination), but only within such period of time ending on the
earlier of (i) the date twelve (12) months following such termination or (ii)
the expiration of the term of the Option as set forth in

                                  6.

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the Option Agreement. If, after termination, the Optionholder does not
exercise his or her Option within the time specified herein, the Option shall
terminate.

           (j)       DEATH OF OPTIONHOLDER. In the event (i) an
Optionholder's Continuous Service terminates as a result of the
Optionholder's death or (ii) the Optionholder dies within the three-month
period after the termination of the Optionholder's Continuous Service for a
reason other than death, then the Option may be exercised (to the extent the
Optionholder was entitled to exercise the Option as of the date of death) by
the Optionholder's estate, by a person who acquired the right to exercise the
Option by bequest or inheritance or by a person designated to exercise the
Option upon the Optionholder's death, but only within the period ending on
the earlier of (1) the date twelve (12) months following the date of death or
(2) the expiration of the term of such Option as set forth in the Option
Agreement. If, after death, the Option is not exercised within the time
specified herein, the Option shall terminate.

8.         COVENANTS OF THE COMPANY.

           (a)       AVAILABILITY OF SHARES. During the terms of the Options,
the Company shall keep available at all times the number of shares of Common
Stock required to satisfy such Options.

           (b)       SECURITIES LAW COMPLIANCE. The Company shall seek to
obtain from each regulatory commission or agency having jurisdiction over the
Plan such authority as may be required to grant Options and to issue and sell
shares of Common Stock upon exercise of the Options; provided, however, that
this undertaking shall not require the Company to register under the
Securities Act the Plan, any Option or any stock issued or issuable pursuant
to any such Option. If, after reasonable efforts, the Company is unable to
obtain from any such regulatory commission or agency the authority which
counsel for the Company deems necessary for the lawful issuance and sale of
stock under the Plan, the Company shall be relieved from any liability for
failure to issue and sell stock upon exercise of such Options unless and
until such authority is obtained.

9.         USE OF PROCEEDS FROM STOCK.

           Proceeds from the sale of stock pursuant to Options shall
constitute general funds of the Company.

10.        MISCELLANEOUS.

           (a)       STOCKHOLDER RIGHTS. No Optionholder shall be deemed to
be the holder of, or to have any of the rights of a holder with respect to,
any shares subject to such Option unless and until such Optionholder has
satisfied all requirements for exercise of the Option pursuant to its terms.

           (b)       NO SERVICE RIGHTS. Nothing in the Plan or any instrument
executed or Option granted pursuant thereto shall confer upon any
Optionholder any right to continue to serve the Company as a Non-Employee
Director or shall affect the right of the Company or an Affiliate to
terminate (i) the employment of an Employee with or without notice and with
or without cause, (ii) the service of a Consultant pursuant to the terms of
such Consultant's agreement with the Company or an Affiliate or (iii) the
service of a Director pursuant to the Bylaws of the Company

                                  7.

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or an Affiliate, and any applicable provisions of the corporate law of the
state in which the Company or the Affiliate is incorporated, as the case may
be.

           (c)       INVESTMENT ASSURANCES. The Company may require an
Optionholder, as a condition of exercising or acquiring stock under any
Option, (i) to give written assurances satisfactory to the Company as to the
Optionholder's knowledge and experience in financial and business matters
and/or to employ a purchaser representative reasonably satisfactory to the
Company who is knowledgeable and experienced in financial and business
matters and that he or she is capable of evaluating, alone or together with
the purchaser representative, the merits and risks of exercising the Option;
and (ii) to give written assurances satisfactory to the Company stating that
the Optionholder is acquiring the stock subject to the Option for the
Optionholder's own account and not with any present intention of selling or
otherwise distributing the stock. The foregoing requirements, and any
assurances given pursuant to such requirements, shall be inoperative if (1)
the issuance of the shares upon the exercise or acquisition of stock under
the Option has been registered under a then currently effective registration
statement under the Securities Act or (2) as to any particular requirement, a
determination is made by counsel for the Company that such requirement need
not be met in the circumstances under the then applicable securities laws.
The Company may, upon advice of counsel to the Company, place legends on
stock certificates issued under the Plan as such counsel deems necessary or
appropriate in order to comply with applicable securities laws, including,
but not limited to, legends restricting the transfer of the stock.

           (d)       WITHHOLDING OBLIGATIONS. The Optionholder may satisfy
any federal, state or local tax withholding obligation relating to the
exercise or acquisition of stock under an Option by any of the following
means (in addition to the Company's right to withhold from any compensation
paid to the Optionholder by the Company) or by a combination of such means:
(i) tendering a cash payment; (ii) authorizing the Company to withhold shares
from the shares of the Common Stock otherwise issuable to the Optionholder as
a result of the exercise or acquisition of stock under the Option, provided,
however, that no shares of Common Stock are withheld with a value exceeding
the minimum amount of tax required to be withheld by law; or (iii) delivering
to the Company owned and unencumbered shares of the Common Stock.

11.        ADJUSTMENTS UPON CHANGES IN STOCK.

           (a)       CAPITALIZATION ADJUSTMENTS. If any change is made in the
stock subject to the Plan, or subject to any Option, without the receipt of
consideration by the Company (through merger, consolidation, reorganization,
recapitalization, reincorporation, stock dividend, dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange
of shares, change in corporate structure or other transaction not involving
the receipt of consideration by the Company), the Plan will be appropriately
adjusted in the type(s), class(es) and maximum number of securities subject
both to the Plan pursuant to subsection 4(a) and to the nondiscretionary
Options specified in Section 5, and the outstanding Options will be
appropriately adjusted in the type(s), class(es) and number of securities and
price per share of stock subject to such outstanding Options. The Board shall
make such adjustments, and its determination shall be final, binding and
conclusive. (The conversion of any convertible securities of the Company
shall not be treated as a transaction "without receipt of consideration" by
the Company.)

                                  8.

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           (b)       DISSOLUTION OR LIQUIDATION. In the event of a
dissolution  or  liquidation of the Company, then all outstanding Options
shall terminate immediately prior to such event.

           (c)       CORPORATE TRANSACTION. In the event of (i) a sale,
exchange, lease or other disposition of all or substantially all of the
securities or assets of the Company, (ii) a merger or consolidation in which
the Company is not the surviving corporation or (iii) a reverse merger in
which the Company is the surviving corporation but the shares of Common Stock
outstanding immediately preceding the merger are converted by virtue of the
merger into other property, whether in the form of securities, cash or
otherwise (each, a "Corporate Transaction"), then with respect to Options
held by Optionholders whose Continuous Service has not terminated, the
vesting of such Options (and the time during which such Options may be
exercised) shall be accelerated in full, and the Options shall terminate if
not exercised at or prior to the Corporate Transaction. With respect to any
other Options outstanding under the Plan, such Options shall terminate if not
exercised prior to the Corporate Transaction.

12.        AMENDMENT OF THE PLAN AND OPTIONS.

           (a)       AMENDMENT OF PLAN. The Board at any time, and from time
to time, may amend the Plan. However, except as provided in Section 11
relating to adjustments upon changes in stock, no amendment shall be
effective unless approved by the stockholders of the Company to the extent
stockholder approval is necessary to satisfy the requirements of Rule 16b-3
or any Nasdaq or securities exchange listing requirements.

           (b)       STOCKHOLDER APPROVAL. The Board may, in its sole
discretion,  submit any other amendment to the Plan for stockholder approval.

           (c)       NO IMPAIRMENT OF RIGHTS. Rights under any Option granted
before amendment of the Plan shall not be impaired by any amendment of the
Plan unless (i) the Company requests the consent of the Optionholder and (ii)
the Optionholder consents in writing.

           (d)       AMENDMENT OF OPTIONS. The Board at any time, and from
time to time, may amend the terms of any one or more Options; provided,
however, that the rights under any Option shall not be impaired by any such
amendment unless (i) the Company requests the consent of the Optionholder and
(ii) the Optionholder consents in writing.

13.        TERMINATION OR SUSPENSION OF THE PLAN.

           (a)       PLAN TERM. The Board may suspend or terminate the Plan
at any time. No Options may be granted under the Plan while the Plan is
suspended or after it is terminated.

           (b)       NO IMPAIRMENT OF RIGHTS. Suspension or termination of
the Plan shall not impair rights and obligations under any Option granted
while the Plan is in effect except with the written consent of the
Optionholder.

                                  9.

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14.        EFFECTIVE DATE OF PLAN.

           The Plan shall become effective on the IPO Date, but no Option
shall be exercised unless and until the Plan has been approved by the
stockholders of the Company, which approval shall be within twelve (12)
months before or after the date the Plan is adopted by the Board.

15.        CHOICE OF LAW.

           All questions concerning the construction, validity and
interpretation of this Plan shall be governed by the law of the State of
California, without regard to such state's conflict of laws rules.

                                  10.