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                                                                    Exhibit 10.1

                                1991 STOCK PLAN OF
                                INCYTE GENOMICS, INC.
                 (As Amended and Restated on February 15, 2001)


SECTION 1.  ESTABLISHMENT AND PURPOSE.

            The Plan was adopted on November 7, 1991, and most recently amended
and restated on February 15, 2001. The purpose of the Plan is to offer selected
employees and consultants an opportunity to acquire a proprietary interest in
the success of the Company, or to increase such interest, by purchasing Shares
of the Company's Stock. The Plan provides both for the direct award or sale of
Shares and for the grant of Options to purchase Shares. Options granted under
the Plan may include Nonstatutory Options as well as ISOs intended to qualify
under section 422 of the Code.

            The Plan is intended to comply in all respects with Rule 16b-3 (or
its successor) under the Exchange Act and shall be construed accordingly.

SECTION 2.  DEFINITIONS.

            (a)  "Board of Directors" shall mean the Board of Directors of the
Company, as constituted from time to time.

            (b)  "Change in Control" shall mean the occurrence of either of the
following events:

            (i)  A change in the composition of the Board of Directors, as a
    result of which fewer than one-half of the incumbent directors are directors
    who either:

                    (A)  Had been directors of the Company 24 months prior to
    such change; or

                    (B)  Were elected, or nominated for election, to the Board
    of Directors with the affirmative votes of at least a majority of the
    directors who had been directors of the Company 24 months prior to such
    change and who were still in office at the time of the election or
    nomination; or

            (ii) Any "person" (as such term is used in sections 13(d) and 14(d)
    of the Exchange Act) by the acquisition or aggregation of securities is or
    becomes the beneficial owner, directly or indirectly, of securities of the
    Company representing 50 percent or more of the combined voting power of the
    Company's then outstanding securities ordinarily (and apart from rights
    accruing under special circumstances) having the right to vote at elections
    of directors (the "Base Capital Stock"); except that any change in the
    relative beneficial ownership of the Company's securities by any person
    resulting solely from a reduction in the aggregate number of outstanding
    shares of Base Capital Stock, and any decrease thereafter in such person's
    ownership of securities, shall be disregarded until such person increases in
    any manner, directly or indirectly, such person's beneficial ownership of
    any securities of the Company.

            (c)  "Code" shall mean the Internal Revenue Code of 1986, as
amended.

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            (d)  "Committee" shall mean a committee of the Board of Directors,
as described in Section 3(a).

            (e)  "Company" shall mean Incyte Genomics, Inc. (formerly Incyte
Pharmaceuticals, Inc.), a Delaware corporation.

            (f)  "Employee" shall mean (i) any individual who is a common-law
employee of the Company or of a Subsidiary or (ii) an independent contractor who
performs services for the Company or a Subsidiary and who is not a member of the
Board of Directors. Service as an independent contractor shall be considered
employment for all purposes of the Plan except the second sentence of Section
4(a).

            (g)  "Exchange Act" shall mean the Securities Exchange Act of 1934,
as amended.

            (h)  "Exercise Price" shall mean the amount for which one Share may
be purchased upon exercise of an Option, as specified by the Committee in the
applicable Stock Option Agreement.

            (i)  "Fair Market Value," with respect to a Share, shall mean the
market price of one Share of Stock, determined by the Committee as follows:

            (i)  If the Stock was traded over-the-counter on the date in
    question but was not traded on The Nasdaq Stock Market, then the Fair Market
    Value shall be equal to the last-transaction price quoted for such date by
    the OTC Bulletin Board or, if not so quoted, shall be equal to the mean
    between the last reported representative bid and asked prices quoted for
    such date by the principal automated inter-dealer quotation system on which
    the Stock is quoted or, if the Stock is not quoted on any such system, by
    the "Pink Sheets" published by the National Quotation Bureau, Inc.;

            (ii)  If the Stock was traded on The Nasdaq Stock Market, then the
    Fair Market Value shall be equal to the last reported sale price quoted for
    such date by The Nasdaq Stock Market;

            (iii)  If the Stock was traded on a United States stock exchange on
    the date in question, then the Fair Market Value shall be equal to the
    closing price reported for such date by the applicable composite-
    transactions report; and

            (iv)  If none of the foregoing provisions is applicable, then the
    Fair Market Value shall be determined by the Committee in good faith on such
    basis as it deems appropriate.

In all cases, the determination of Fair Market Value by the Committee shall be
conclusive and binding on all persons.

            (j)  "ISO" shall mean an employee incentive stock option described
in section 422(b) of the Code.

            (k)  "Nonstatutory Option" shall mean an employee stock option not
described in sections 422(b) or 423(b) of the Code.

            (l)  "Offeree" shall mean an individual to whom the Committee has
offered the right to

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acquire Shares under the Plan (other than upon exercise of an Option).

            (m)  "Option" shall mean an ISO or Nonstatutory Option granted under
the Plan and entitling the holder to purchase Shares.

            (n)  "Optionee" shall mean an individual who holds an Option.

            (o)  "Plan" shall mean this Amended and Restated 1991 Stock Plan of
Incyte Genomics, Inc.

            (p)  "Purchase Price" shall mean the consideration for which one
Share may be acquired under the Plan (other than upon exercise of an Option), as
specified by the Committee.

            (q)  "Service" shall mean service as an Employee.

            (r)  "Share" shall mean one share of Stock, as adjusted in
accordance with Section 9 (if applicable).

            (s)  "Stock" shall mean the Common Stock, $.001 par value, of the
Company.

            (t)  "Stock Option Agreement" shall mean the agreement between the
Company and an Optionee which contains the terms, conditions and restrictions
pertaining to his or her Option.

            (u)  "Stock Purchase Agreement" shall mean the agreement between the
Company and an Offeree who acquires Shares under the Plan which contains the
terms, conditions and restrictions pertaining to the acquisition of such Shares.

            (v)  "Subsidiary" shall mean any corporation, if the Company and/or
one or more other Subsidiaries own not less than 50 percent of the total
combined voting power of all classes of outstanding stock of such corporation. A
corporation that attains the status of a Subsidiary on a date after the adoption
of the Plan shall be considered a Subsidiary commencing as of such date.

            (w)  "Total and Permanent Disability" shall mean that the Optionee
is unable to engage in any substantial gainful activity by reason of any
medically determinable physical or mental impairment which can be expected to
result in death or which has lasted, or can be expected to last, for a
continuous period of not less than one year.

SECTION 3.  ADMINISTRATION.

            (a)  Committee Composition. The Plan shall be administered by the
Committee. The Committee shall consist of two or more directors of the Company
who shall satisfy the requirements of Rule 16b-3 (or its successor) under the
Exchange Act with respect to the grant of Awards to persons who are officers or
directors of the Company under Section 16 of the Exchange Act or the Board
itself. The Board may also appoint one or more separate committees of the Board,
each composed of one or more directors of the Company who need not qualify under
Rule 16b-3, who may administer the Plan with respect to Employees who are not
considered officers or directors of the Company under Section 16 of the Exchange
Act, may grant Shares and Options under the Plan to such Employees and may
determine all terms of such grants.

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            (b)   Committee Procedures. The Board of Directors shall designate
one of the members of the Committee as chairman. The Committee may hold meetings
at such times and places as it shall determine. The acts of a majority of the
Committee members present at meetings at which a quorum exists, or acts reduced
to or approved in writing by all Committee members, shall be valid acts of the
Committee.

            (c)   Committee Responsibilities. Subject to the provisions of the
Plan, the Committee shall have full authority and discretion to take the
following actions:

            (i)   To interpret the Plan and to apply its provisions;

            (ii)  To adopt, amend or rescind rules, procedures and forms
    relating to the Plan;

            (iii) To authorize any person to execute, on behalf of the Company,
    any instrument required to carry out the purposes of the Plan;

            (iv)  To determine when Shares are to be awarded or offered for sale
    and when Options are to be granted under the Plan;

            (v)   To select the Offerees and Optionees;

            (vi)  To determine the number of Shares to be offered to each
    Offeree or to be made subject to each Option;

            (vii) To prescribe the terms and conditions of each award or sale of
    Shares, including (without limitation) the Purchase Price, and to specify
    the provisions of the Stock Purchase Agreement relating to such award or
    sale;

            (viii)  To prescribe the terms and conditions of each Option,
    including (without limitation) the Exercise Price, to determine whether such
    Option is to be classified as an ISO or as a Nonstatutory Option, and to
    specify the provisions of the Stock Option Agreement relating to such
    Option;

            (ix)    To amend any outstanding Stock Purchase Agreement or Stock
    Option Agreement, subject to applicable legal restrictions and to the
    consent of the Offeree or Optionee who entered into such agreement;

            (x)   To prescribe the consideration for the grant of each Option or
    other right under the Plan and to determine the sufficiency of such
    consideration; and

            (xi)  To take any other actions deemed necessary or advisable for
    the administration of the Plan.

All decisions, interpretations and other actions of the Committee shall be final
and binding on all Offerees, all Optionees, and all persons deriving their
rights from an Offeree or Optionee.  No member of the Committee shall be liable
for any action that he or she has taken or has failed to take in good faith with
respect to the Plan, any Option, or any right to acquire Shares under the Plan.

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SECTION 4.  ELIGIBILITY.

            (a)  General Rule. Only Employees, as defined in Section 2(f), shall
be eligible for designation as Optionees or Offerees by the Committee. In
addition, only individuals who are employed as common-law employees by the
Company or a Subsidiary shall be eligible for the grant of ISOs.

            (b)  Ten-Percent Stockholders. An Employee who owns more than 10
percent of the total combined voting power of all classes of outstanding stock
of the Company or any of its Subsidiaries shall not be eligible for the grant of
an ISO unless (i) the Exercise Price is at least 110 percent of the Fair Market
Value of a Share on the date of grant and (ii) such ISO by its terms is not
exercisable after the expiration of five years from the date of grant.

            (c)  Attribution Rules. For purposes of Subsection (b) above, in
determining stock ownership, an Employee shall be deemed to own the stock owned,
directly or indirectly, by or for such Employee's brothers, sisters, spouse,
ancestors and lineal descendants. Stock owned, directly or indirectly, by or for
a corporation, partnership, estate or trust shall be deemed to be owned
proportionately by or for its stockholders, partners or beneficiaries. Stock
with respect to which such Employee holds an option shall not be counted.

            (d)  Outstanding Stock. For purposes of Subsection (b) above,
"outstanding stock" shall include all stock actually issued and outstanding
immediately after the grant. "Outstanding stock" shall not include shares
authorized for issuance under outstanding options held by the Employee or by any
other person.

SECTION 5.  STOCK SUBJECT TO PLAN.

            (a)  Basic Limitation. Shares offered under the Plan shall be
authorized but unissued Shares or treasury Shares. The aggregate number of
Shares which may be issued under the Plan (upon exercise of Options or other
rights to acquire Shares) shall not exceed 19,900,000 Shares, subject to
adjustment pursuant to Section 9. The number of Shares that are subject to
Options or other rights outstanding at any time under the Plan shall not exceed
the number of Shares that then remain available for issuance under the Plan. The
Company, during the term of the Plan, shall at all times reserve and keep
available sufficient Shares to satisfy the requirements of the Plan.

            (b)  Additional Shares. In the event that any outstanding Option or
other right for any reason expires or is canceled or otherwise terminated, the
Shares allocable to the unexercised portion of such Option or other right shall
again be available for the purposes of the Plan. In the event that Shares issued
under the Plan are reacquired by the Company pursuant to any forfeiture
provision, right of repurchase or right of first refusal, such Shares shall
again be available for the purposes of the Plan.

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SECTION 6.  TERMS AND CONDITIONS OF AWARDS OR SALES.

            (a)  Stock Purchase Agreement. Each award or sale of Shares under
the Plan (other than upon exercise of an Option) shall be evidenced by a Stock
Purchase Agreement between the Offeree and the Company. Such award or sale shall
be subject to all applicable terms and conditions of the Plan and may be subject
to any other terms and conditions which are not inconsistent with the Plan and
which the Committee deems appropriate for inclusion in a Stock Purchase
Agreement. The provisions of the various Stock Purchase Agreements entered into
under the Plan need not be identical.

            (b)  Duration of Offers and Nontransferability of Rights. Any right
to acquire Shares under the Plan (other than an Option) shall automatically
expire if not exercised by the Offeree within 30 days after the grant of such
right was communicated to the Offeree by the Committee. Such right shall not be
transferable and shall be exercisable only by the Offeree to whom such right was
granted.

            (c)  Purchase Price. The Purchase Price of Shares to be offered
under the Plan shall not be less than the par value of such Shares. Subject to
the preceding sentence, the Purchase Price shall be determined by the Committee
at its sole discretion. The Purchase Price shall be payable in a form described
in Section 8.

            (d)  Withholding Taxes. As a condition to the award, purchase,
vesting or sale of Shares, the Offeree shall make such arrangements as the
Committee may require for the satisfaction of any federal, state, local or
foreign withholding tax obligations that may arise in connection with such
Shares. The Committee may permit the Offeree to satisfy all or part of his or
her tax obligations related to such Shares by having the Company withhold a
portion of any Shares that otherwise would be issued to him or her or by
surrendering any Shares that previously were acquired by him or her. The Shares
withheld or surrendered shall be valued at their Fair Market Value on the date
when taxes otherwise would be withheld in cash. The payment of taxes by
assigning Shares to the Company, if permitted by the Committee, shall be subject
to such restrictions as the Committee may impose, including any restrictions
required by rules of the Securities and Exchange Commission.

            (e)  Restrictions on Transfer of Shares. Any Shares awarded or sold
under the Plan shall be subject to such special forfeiture conditions, rights of
repurchase, rights of first refusal and other transfer restrictions as the
Committee may determine. Such restrictions shall be set forth in the applicable
Stock Purchase Agreement and shall apply in addition to any general restrictions
that may apply to all holders of Shares.

SECTION 7.  TERMS AND CONDITIONS OF OPTIONS.

            (a)  Stock Option Agreement. Each grant of an Option under the Plan
shall be evidenced by a Stock Option Agreement between the Optionee and the
Company. Such Option shall be subject to all applicable terms and conditions of
the Plan and may be subject to any other terms and conditions which are not
inconsistent with the Plan and which the Committee deems appropriate for
inclusion in a Stock Option Agreement. The provisions of the various Stock
Option Agreements entered into under the Plan need not be identical.

            (b)  Number of Shares. Each Stock Option Agreement shall specify the
number of Shares that are subject to the Option and shall provide for the
adjustment of such number in accordance with Section 9. The Stock Option
Agreement shall also specify whether the Option is an ISO or a

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Nonstatutory Option. Options granted to any Optionee in a single calendar year
shall in no event cover more than 800,000 Shares, subject to adjustment in
accordance with Section 9.

            (c)  Exercise Price. Each Stock Option Agreement shall specify the
Exercise Price. The Exercise Price of an ISO shall not be less than 100 percent
of the Fair Market Value of a Share on the date of grant, and a higher
percentage may be required by Section 4(b). The Exercise Price of a Nonstatutory
Option shall not be less than 100 percent of the Fair Market Value of a Share on
the date of grant. Subject to the preceding two sentences, the Exercise Price
under any Option shall be determined by the Committee at its sole discretion.
The Exercise Price shall be payable in a form described in Section 8.

            (d)  Withholding Taxes. As a condition to the exercise of an Option,
the Optionee shall make such arrangements as the Committee may require for the
satisfaction of any federal, state, local or foreign withholding tax obligations
that may arise in connection with such exercise. The Optionee shall also make
such arrangements as the Committee may require for the satisfaction of any
federal, state, local or foreign withholding tax obligations that may arise in
connection with the disposition of Shares acquired by exercising an Option. The
Committee may permit the Optionee to satisfy all or part of his or her tax
obligations related to the Option by having the Company withhold a portion of
any Shares that otherwise would be issued to him or her or by surrendering any
Shares that previously were acquired by him or her. Such Shares shall be valued
at their Fair Market Value on the date when taxes otherwise would be withheld in
cash. The payment of taxes by assigning Shares to the Company, if permitted by
the Committee, shall be subject to such restrictions as the Committee may
impose, including any restrictions required by rules of the Securities and
Exchange Commission.

            (e)  Exercisability. Each Stock Option Agreement shall specify the
date when all or any installment of the Option is to become exercisable. A Stock
Option Agreement may provide for accelerated exercisability in the event of the
Optionee's death, Total and Permanent Disability or retirement or other events.

            (f)  Effect of Change in Control. The Committee may determine, at
the time of granting an Option or thereafter, that such Option shall become
exercisable on an accelerated basis in the event that a Change in Control occurs
with respect to the Company. If the Committee finds that there is a reasonable
possibility that, within the succeeding six months, a Change in Control will
occur with respect to the Company, then the Committee may determine that all
outstanding Options shall be exercisable on an accelerated basis.

            (g)  Term. The Stock Option Agreement shall specify the term of the
Option. The term shall not exceed 10 years from the date of grant, except as
otherwise provided in Section 4(b). Subject to the preceding sentence, the
Committee at its sole discretion shall determine when an Option is to expire.

            (h)  Nontransferability. Except as may be provided in the applicable
Stock Option Agreement with respect to a Nonstatutory Option, no Option shall be
transferable by the Optionee other than by will, by beneficiary designation
delivered to the Company, or by the laws of descent and distribution. An Option
may be exercised during the lifetime of the Optionee only by the Optionee or by
the Optionee's guardian or legal representative. No Option or interest therein
may be transferred, assigned, pledged or hypothecated by the Optionee during his
or her lifetime, whether by operation of law or otherwise, or be made subject to
execution, attachment or similar process.

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            (i)   Termination of Service (Except by Death). Except as may be
provided in the applicable Stock Option Agreement, if an Optionee's Service
terminates for any reason other than the Optionee's death, then such Optionee's
Option(s) shall expire on the earliest of the following occasions:

            (i)   The expiration date determined pursuant to Subsection (g)
    above;

            (ii)  The date 90 days after the termination of the Optionee's
    Service for any reason other than Total and Permanent Disability; or

            (iii) The date six months after the termination of the Optionee's
    Service by reason of Total and Permanent Disability.

The Optionee may exercise all or part of his or her Option(s) at any time before
the expiration of such Option(s) under the preceding sentence, but only to the
extent that such Option(s) had become exercisable before the Optionee's Service
terminated or became exercisable as a result of the termination.  The balance of
such Option(s) shall lapse when the Optionee's Service terminates.  In the event
that the Optionee dies after the termination of the Optionee's Service but
before the expiration of the Optionee's Option(s), all or part of such Option(s)
may be exercised (prior to expiration) by the executors or administrators of the
Optionee's estate or by any person who has acquired such Option(s) directly from
the Optionee by bequest, beneficiary designation or inheritance, but only to the
extent that such Option(s) had become exercisable before the Optionee's Service
terminated or became exercisable as a result of the termination.

            (j)   Leaves of Absence. Except as may be provided in the applicable
Stock Option Agreement, for purposes of Subsection (i) above, Service shall be
deemed to continue while the Optionee is on military leave, sick leave or other
bona fide leave of absence (as determined by the Committee). The foregoing
notwithstanding, in the case of an ISO granted under the Plan, Service shall not
be deemed to continue beyond the first 90 days of such leave, unless the
Optionee's reemployment rights are guaranteed by statute or by contract.

            (k)   Death of Optionee. Except as may be provided in the applicable
Stock Option Agreement, if an Optionee dies while he or she is in Service, then
such Optionee's Option(s) shall expire on the earlier of the following dates:

            (i)   The expiration date determined pursuant to Subsection (g)
    above; or

            (ii)  The date six months after the Optionee's death.

All or part of the Optionee's Option(s) may be exercised at any time before the
expiration of such Option(s) under the preceding sentence by the executors or
administrators of the Optionee's estate or by any person who has acquired such
Option(s) directly from the Optionee by bequest, beneficiary designation or
inheritance, but only to the extent that such Option(s) had become exercisable
before the Optionee's death or became exercisable as a result of the Optionee's
death.  The balance of such Option(s) shall lapse when the Optionee dies.

            (l)   No Rights as a Stockholder. An Optionee, or a transferee of an
Optionee, shall have no rights as a stockholder with respect to any Shares
covered by his or her Option until he or she

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becomes entitled, pursuant to the terms of such Option, to receive such Shares.
No adjustments shall be made, except as provided in Section 9.

            (m)  Modification, Extension and Assumption of Options.  Within the
limitations of the Plan, the Committee may modify, extend or assume outstanding
Options or may accept the cancellation of outstanding Options (whether granted
by the Company or another issuer) in return for the grant of new Options for the
same or a different number of Shares and at the same or a different Exercise
Price.  The foregoing notwithstanding, no modification of an Option shall,
without the consent of the Optionee, impair such Optionee's rights or increase
his or her obligations under such Option.

            (n)  Restrictions on Transfer of Shares. Any Shares issued upon
exercise of an Option may be subject to such special forfeiture conditions,
rights of repurchase, rights of first refusal and other transfer restrictions as
the Committee may determine. Such restrictions shall be set forth in the
applicable Stock Option Agreement and shall apply in addition to any general
restrictions that may apply to all holders of Shares.

SECTION 8.  PAYMENT FOR SHARES.

            (a)  General Rule. The entire Purchase Price or Exercise Price of
Shares issued under the Plan shall be payable in lawful money of the United
States of America at the time when such Shares are purchased, except as provided
in Subsections (b), (c), (d), (e) and (f) below.

            (b)  Surrender of Stock. To the extent that a Stock Option Agreement
so provides, payment may be made all or in part with Shares which have already
been owned by the Optionee or the Optionee's representative for more than six
months and which are surrendered to the Company in good form for transfer. Such
Shares shall be valued at their Fair Market Value on the date when the new
Shares are purchased under the Plan.

            (c)  Services Rendered. At the discretion of the Committee, Shares
may be awarded under the Plan in consideration of services rendered to the
Company or a Subsidiary prior to the award. If Shares are awarded without the
payment of a Purchase Price in cash, the Committee shall make a determination
(at the time of the award) of the value of the services rendered by the Offeree
and the sufficiency of the consideration to meet the requirements of Section
6(c).

            (d)  Promissory Note. To the extent that a Stock Option Agreement or
Stock Purchase Agreement so provides, a portion of the Exercise Price or
Purchase Price (as the case may be) of Shares issued under the Plan may be paid
with a full-recourse promissory note, provided that (i) the par value of such
Shares must be paid in lawful money of the United States of America at the time
when such Shares are purchased, (ii) the Shares are pledged as security for
payment of the principal amount of the promissory note and interest thereon and
(iii) the interest rate payable under the terms of the promissory note shall not
be less than the minimum rate (if any) required to avoid the imputation of
additional interest under the Code. Subject to the foregoing, the Committee (at
its sole discretion) shall specify the term, interest rate, amortization
requirements (if any) and other provisions of such note.

            (e)  Exercise/Sale. To the extent that a Stock Option Agreement so
provides, payment may be made all or in part by the delivery (on a form
prescribed by the Company) of an irrevocable direction to a securities broker
approved by the Company to sell Shares and to deliver all or part of the sales
proceeds to the Company in payment of all or part of the Exercise Price and any

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withholding taxes.

            (f)  Exercise/Pledge.  To the extent that a Stock Option Agreement
so provides, payment may be made all or in part by the delivery (on a form
prescribed by the Company) of an irrevocable direction to pledge Shares to a
securities broker or lender approved by the Company, as security for a loan, and
to deliver all or part of the loan proceeds to the Company in payment of all or
part of the Exercise Price and any withholding taxes.

SECTION 9.  ADJUSTMENT OF SHARES.

            (a)  General. In the event of a subdivision of the outstanding
Stock, a declaration of a dividend payable in Shares, a declaration of a
dividend payable in a form other than Shares in an amount that has a material
effect on the value of Shares, a combination or consolidation of the outstanding
Stock into a lesser number of Shares, a recapitalization, a spinoff, a
reclassification or a similar occurrence, the Committee shall make appropriate
adjustments in one or more of (i) the number of Shares available for future
grants under Section 5, (ii) the limit set forth in Section 7(b), (iii) the
number of Shares covered by each outstanding Option or (iv) the Exercise Price
under each outstanding Option.

            (b)  Reorganizations. In the event that the Company is a party to a
merger or other reorganization, outstanding Options shall be subject to the
agreement of merger or reorganization. Such agreement may provide, without
limitation, (i) for the assumption of outstanding Options by the surviving
corporation or its parent, (ii) for their continuation by the Company, if the
Company is a surviving corporation, (iii) for payment of a cash settlement equal
to the difference between the amount to be paid for one Share pursuant to such
agreement and the Exercise Price or (iv) for the acceleration of their
exercisability followed by the cancellation of Options not exercised, in all
cases without the Optionees' consent. Any cancellation shall not occur until
after such acceleration is effective and Optionees have been notified of such
acceleration.

            (c)  Reservation of Rights. Except as provided in this Section 9, an
Optionee or Offeree shall have no rights by reason of (i) any subdivision or
consolidation of shares of stock of any class, (ii) the payment of any dividend
or (iii) any other increase or decrease in the number of shares of stock of any
class. Any issue by the Company of shares of stock of any class, or securities
convertible into shares of stock of any class, shall not affect, and no
adjustment by reason thereof shall be made with respect to, the number or
Exercise Price of Shares subject to an Option. The grant of an Option pursuant
to the Plan shall not affect in any way the right or power of the Company to
make adjustments, reclassifications, reorganizations or changes of its capital
or business structure, to merge or consolidate or to dissolve, liquidate, sell
or transfer all or any part of its business or assets.

SECTION 10.  SECURITIES LAWS.

            Shares shall not be issued under the Plan unless the issuance and
delivery of such Shares comply with (or are exempt from) all applicable
requirements of law, including (without limitation) the Securities Act of 1933,
as amended, the Exchange Act, the rules and regulations promulgated thereunder,
state securities laws and regulations, and the regulations of any stock exchange
on which the Company's securities may then be listed.

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SECTION 11.  NO EMPLOYMENT RIGHTS.

             No provision of the Plan, nor any right or Option granted under the
Plan, shall be construed to give any person any right to become, to be treated
as, or to remain an Employee. The Company and its Subsidiaries reserve the right
to terminate any person's Service at any time and for any reason.

SECTION 12.  DURATION AND AMENDMENTS.

             (a)  Term of the Plan. The Plan, as amended and restated as set
forth herein, shall become effective as of February 15, 2001. In the event the
Company's stockholders fail to approve the amendment to the Plan increasing the
number of shares issuable hereunder at the 2001 annual meeting of stockholders,
any Option grants or Stock awards made in excess of an aggregate of 17,400,000
Shares shall be null and void. The Plan shall terminate automatically on
February 15, 2011 and may be terminated on any earlier date pursuant to
Subsection (b) below.

             (b)  Right to Amend or Terminate the Plan. The Board of Directors
may amend, suspend or terminate the Plan at any time and for any reason. An
amendment of the Plan shall be subject to the approval of the Company's
stockholders to the extent required by applicable laws, regulations, rules,
listing standards or other requirements, including (without limitation) Rule
16b-3 under the Exchange Act. Stockholder approval shall not be required for any
other amendment of the Plan.

             (c)  Effect of Amendment or Termination. No Shares shall be issued
or sold under the Plan after the termination thereof, except upon exercise of an
Option granted prior to such termination. The termination of the Plan, or any
amendment thereof, shall not affect any Share previously issued or any Option
previously granted under the Plan.

SECTION 13.  EXECUTION.

             To record the amendment and restatement of the Plan by the Board of
Directors on February 15, 2001, the Company has caused its authorized officer to
execute the same.


                                           INCYTE GENOMICS, INC.



                                           By  /s/ Roy A. Whitfield
                                              __________________________________

                                           Its  Chief Executive Officer
                                               _________________________________

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