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                        GENAISSANCE PHARMACEUTICALS, INC.

                 2000 AMENDED AND RESTATED EQUITY INCENTIVE PLAN

1.       PURPOSE.
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     This Genaissance Pharmaceuticals, Inc. 2000 Amended and Restated Equity
Incentive Plan (the "Plan") amends and restates the Genaissance Pharmaceuticals,
Inc. Stock Option Plan by providing for the grant of equity incentives of
various forms in the Company, including restricted stock awards. The purpose of
the Plan is to attract and retain directors and key employees and consultants of
the Company and its Affiliates, to provide an incentive for them to achieve
performance goals, and to enable them to participate in the growth of the
Company by granting Awards with respect to the Company's Common Stock. Certain
capitalized terms used herein are defined in Section 9 below.

2.       ADMINISTRATION.
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     The Plan shall be administered by the Committee; provided, that the Board
may in any instance perform any of the functions of the Committee hereunder. The
Committee shall select the Participants to receive Awards and shall determine
the terms and conditions of the Awards. The Committee shall have authority to
adopt, alter and repeal such administrative rules, guidelines and practices
governing the operation of the Plan as it shall from time to time consider
advisable, and to interpret the provisions of the Plan. The Committee's
decisions shall be final and binding. To the extent permitted by applicable law,
the Committee may delegate to one or more executive officers of the Company the
power to make Awards to Participants who are not Reporting Persons or Covered
Employees and all determinations under the Plan with respect thereto, provided
that the Committee shall fix the maximum amount of such Awards for all such
Participants and a maximum for any one Participant.

3.       ELIGIBILITY.
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         All directors and all employees and consultants of the Company or any
Affiliate capable of contributing to the successful performance of the Company
are eligible to be Participants in the Plan. Incentive Stock Options may be
granted only to persons eligible to receive such Options under the Code.

4.       STOCK AVAILABLE FOR AWARDS.
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     (a) AMOUNT. Subject to adjustment under subsection (b), Awards may be made
under the Plan for up to 3,557,375 shares of Common Stock. If any Award expires
or is terminated unexercised or is forfeited or settled in a manner that results
in fewer shares outstanding than were awarded, the shares subject to such Award,
to the extent of such expiration, termination, forfeiture or decrease, shall
again be available for award under the Plan. Common Stock issued through the
assumption or substitution of outstanding grants from an acquired company shall
not reduce the shares available for Awards under the Plan. Shares issued under
the Plan may consist of authorized but unissued shares or treasury shares.

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     (b) ADJUSTMENT. In the event that the Committee determines that any stock
dividend, extraordinary cash dividend, recapitalization, reorganization, merger,
consolidation, split-up, spin-off, combination, exchange of shares or other
transaction affects the Common Stock such that an adjustment is required in
order to preserve the benefits intended to be provided by the Plan, then the
Committee (subject in the case of Incentive Stock Options to any limitation
required under the Code) shall equitably adjust any or all of (i) the number and
kind of shares in respect of which Awards may be made under the Plan, (ii) the
number and kind of shares subject to outstanding Awards and (iii) the exercise
price with respect to any of the foregoing, provided that the number of shares
subject to any Award shall always be a whole number, and if considered
appropriate, the Committee may make provision for a cash payment with respect to
an outstanding Award.

     (c) LIMIT ON INDIVIDUAL GRANTS. The maximum number of shares of Common
Stock subject to Options and Stock Appreciation Rights that may be granted to
any Participant in the aggregate in any calendar year shall not exceed
1,000,000, and the maximum number of shares of Common Stock that may be granted
as Restricted Stock or Unrestricted Stock Awards, with respect to which
performance goals apply under Section 7 below, to any Participant in the
aggregate in any calendar year shall not exceed 1,000,000, subject to adjustment
under subsection (b).

5.       STOCK OPTIONS.
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     (a) GRANT OF OPTIONS. Subject to the provisions of the Plan, the Committee
may grant options ("Options") to purchase shares of Common Stock (i) complying
with the requirements of Section 422 of the Code or any successor provision and
any regulations thereunder ("Incentive Stock Options") and (ii) not intended to
comply with such requirements ("Nonstatutory Stock Options"). The Committee
shall determine the number of shares subject to each Option and the exercise
price therefor, which shall not be less than 100% of the Fair Market Value of
the Common Stock on the date of grant with respect to Incentive Stock Options.
Nonstatutory Stock Options may be granted at such prices as the Committee may
determine. No Incentive Stock Options may be granted hereunder more than ten
years after the effective date of the Plan.

     (b) TERMS AND CONDITIONS. Each Option shall be exercisable at such times
and subject to such terms and conditions as the Committee may specify in the
applicable grant or thereafter. The Committee may impose such conditions with
respect to the exercise of Options, including conditions relating to applicable
federal or state securities laws, as it considers necessary or advisable.

     (c) PAYMENT. No shares shall be delivered pursuant to any exercise of an
Option until payment in full of the exercise price therefor is received by the
Company. Such payment may be made in whole or in part in cash or, to the extent
permitted by the Committee at or after the grant of the Option, by delivery of a
note or other commitment satisfactory to the Committee or shares of Common Stock
owned by the optionee valued at their Fair Market Value on the date of delivery,
or such other lawful consideration, including a payment commitment of a
financial or brokerage institution, as the Committee may determine.

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6.       STOCK APPRECIATION RIGHTS.
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     (a) GRANT OF SARS. Subject to the provisions of the Plan, the Committee may
grant rights to receive any excess in value of shares of Common Stock over the
exercise price ("Stock Appreciation Rights" or "SARs"). The Committee shall
determine at the time of grant or thereafter whether SARs are settled in cash,
Common Stock or other securities of the Company, Awards or other property, and
may define the manner of determining the excess in value of the shares of Common
Stock.

     (b) EXERCISE PRICE. The Committee shall fix the exercise price of each SAR
or specify the manner in which the price shall be determined.

7.       STOCK AWARDS.
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     (a) GRANT OF RESTRICTED OR UNRESTRICTED STOCK AWARDS. The Committee may
grant shares of Common Stock subject to forfeiture ("Restricted Stock") and
determine the duration of the period (the "Restricted Period") during which, and
the conditions under which, the shares may be forfeited to the Company and the
other terms and conditions of such Awards. Shares of Restricted Stock may not be
sold, assigned, transferred, pledged or otherwise encumbered, except as
permitted by the Committee, during the Restricted Period. Shares of Restricted
Stock shall be evidenced in such manner as the Committee may determine. Any
certificates issued in respect of shares of Restricted Stock shall be registered
in the name of the Participant and unless otherwise determined by the Committee,
deposited by the Participant, together with a stock power endorsed in blank,
with the Company. At the expiration of the Restricted Period, the Company shall
deliver such certificates to the Participant or if the Participant has died, to
the Participant's Designated Beneficiary. The Committee also may make Awards of
shares of Common Stock that are not subject to restrictions or forfeiture, on
such terms and conditions as the Committee may determine from time to time
("Unrestricted Stock").

     (b) PERFORMANCE GOALS. The Committee may establish performance goals for
the granting of Restricted Stock or Unrestricted Stock Awards or the lapse of
risk of forfeiture of Restricted Stock. Such performance goals may be based on
earnings per share, revenues, sales or expense targets of the Company or any
subsidiary or division thereof, stock price, or such other business criteria as
the Committee may determine. The achievement of the performance goals shall be
determined by the Committee. Shares of Restricted Stock or Unrestricted Stock
may be issued for no cash consideration, such minimum consideration as may be
required by applicable law or such other consideration as the Committee may
determine.

8.       GENERAL PROVISIONS APPLICABLE TO AWARDS.
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     (a) DOCUMENTATION. Each Award under the Plan shall be evidenced by a
writing delivered to the Participant or agreement executed by the Participant
specifying the terms and conditions thereof and containing such other terms and
conditions not inconsistent with the provisions of the Plan as the Committee
considers necessary or advisable to achieve the purposes of the Plan or to
comply with applicable tax and regulatory laws and accounting principles.

     (b) COMMITTEE DISCRETION. Each type of Award may be made alone, in addition
to or in relation to any other Award. The terms of each type of Award need not
be identical, and the

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Committee need not treat Participants uniformly. Except as
otherwise provided by the Plan or a particular Award, any determination with
respect to an Award may be made by the Committee at the time of grant or at any
time thereafter.

     (c) DIVIDENDS AND CASH AWARDS. In the discretion of the Committee, any
Award under the Plan may provide the Participant with (i) dividends or dividend
equivalents payable (in cash or in the form of Awards under the Plan) currently
or deferred with or without interest and (ii) cash payments in lieu of or in
addition to an Award.

     (d) TERMINATION OF SERVICE. The Committee shall determine the effect on an
Award of the disability, death, retirement or other termination of service of a
Participant and the extent to which, and the period during which, the
Participant's legal representative, guardian or Designated Beneficiary may
receive payment of an Award or exercise rights thereunder.

     (e) CHANGE IN CONTROL. In order to preserve a Participant's rights under an
Award in the event of a change in control of the Company (as defined by the
Committee), the Committee in its discretion may, at the time an Award is made or
at any time thereafter, take one or more of the following actions: (i) provide
for the acceleration of any time period relating to the exercise or payment of
the Award, (ii) provide for payment to the Participant of cash or other property
with a Fair Market Value equal to the amount that would have been received upon
the exercise or payment of the Award had the Award been exercised or paid upon
the change in control, (iii) adjust the terms of the Award in a manner
determined by the Committee to reflect the change in control, (iv) cause the
Award to be assumed, or new rights substituted therefor, by another entity, or
(v) make such other provision as the Committee may consider equitable to
Participants and in the best interests of the Company.

     (f) TRANSFERABILITY. In the discretion of the Committee, any Award may be
made transferable upon such terms and conditions and to such extent as the
Committee determines, provided that Incentive Stock Options may be transferable
only to the extent permitted by the Code. The Committee may in its discretion
waive any restriction on transferability.

     (g) WITHHOLDING TAXES. The Participant shall pay to the Company, or make
provision satisfactory to the Committee for payment of, any taxes required by
law to be withheld in respect of Awards under the Plan no later than the date of
the event creating the tax liability. The Company and its Affiliates may, to the
extent permitted by law, deduct any such tax obligations from any payment of any
kind due to the Participant hereunder or otherwise. In the Committee's
discretion, the minimum tax obligations required by law to be withheld in
respect of Awards may be paid in whole or in part in shares of Common Stock,
including shares retained from the Award creating the tax obligation, valued at
their Fair Market Value on the date of retention or delivery.

     (h) FOREIGN NATIONALS. Awards may be made to Participants who are foreign
nationals or employed outside the United States on such terms and conditions
different from those specified in the Plan as the Committee considers necessary
or advisable to achieve the purposes of the Plan or to comply with applicable
laws.

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     (i) AMENDMENT OF AWARD. The Committee may amend, modify, or terminate any
outstanding Award, including substituting therefor another Award of the same or
a different type, changing the date of exercise or realization and converting an
Incentive Stock Option to a Nonstatutory Stock Option. Any such action shall
require the Participant's consent unless:

          (i) In the case of a termination of, or a reduction in the number of
shares issuable under, an Option, any time period relating to the exercise of
such Option or the eliminated portion, as the case may be, is waived or
accelerated before such termination or reduction (and in such case the Committee
may provide for the Participant to receive cash or other property equal to the
net value that would have been received upon exercise of the terminated Option
or the eliminated portion, as the case may be); or

          (ii) In any other case, the Committee determines that the action,
taking into account any related action, would not materially and adversely
affect the Participant.

9.       CERTAIN DEFINITIONS.
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          "Affiliate" means any business entity in which the Company owns
directly or indirectly 50% or more of the total voting power or has a
significant financial interest as determined by the Committee.

          "Award" means any Option, Stock Appreciation Right, Restricted Stock,
or Unrestricted Stock granted under the Plan.

          "Board" means the Board of Directors of the Company.

          "Code" means the Internal Revenue Code of 1986, as amended from time
to time, or any successor law.

          "Committee" means one or more committees each comprised of not less
than two members of the Board appointed by the Board to administer the Plan or a
specified portion thereof. Unless otherwise determined by the Board, if a
Committee is authorized to grant Awards to a Reporting Person or a Covered
Employee, each member shall be a "non-employee director" within the meaning of
Rule 16b-3 under the Exchange Act or an "outside director" within the meaning of
Section 162(m) of the Code, respectively.

          "Common Stock" or "Stock" means the Common Stock, $.001 par value,
of the Company.

          "Company" Genaissance Pharmaceuticals, Inc. a Delaware corporation.

          "Covered Employee" means a "covered employee" within the meaning of
Section 162(m) of the Code.

          "Designated Beneficiary" means the beneficiary designated by a
Participant, in a manner determined by the Committee, to receive amounts due or
exercise rights of the Participant in the event of the Participant's death. In
the absence of an effective designation by a Participant, "Designated
Beneficiary" means the Participant's estate.

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          "Exchange Act" means the Securities Exchange Act of 1934, as amended
from time to time, or any successor law.

          "Fair Market Value" means, with respect to Common Stock or any other
property, the fair market value of such property as determined by the Committee
in good faith or in the manner established by the Committee from time to time.

          "Participant" means a person selected by the Committee to receive an
Award under the Plan.

          "Reporting Person" means a person subject to Section 16 of the
Exchange Act.

10.      MISCELLANEOUS.

     (a) NO RIGHT TO EMPLOYMENT. No person shall have any claim or right to be
granted an Award. Neither the adoption, maintenance, nor operation of the Plan
nor any Award hereunder shall confer upon any employee or consultant of the
Company or of any Affiliate any right with respect to the continuance of his/her
employment by or other service with the Company or any such Affiliate nor shall
they interfere with the rights of the Company (or Affiliate) to terminate any
employee at any time or otherwise change the terms of employment, including,
without limitation, the right to promote, demote or otherwise re-assign any
employee from one position to another within the Company or any Affiliate.

     (b) NO RIGHTS AS STOCKHOLDER. Subject to the provisions of the applicable
Award, no Participant or Designated Beneficiary shall have any rights as a
stockholder with respect to any shares of Common Stock to be issued under the
Plan until he or she becomes the holder thereof. A Participant to whom
Restricted Stock or Unrestricted Stock is awarded shall be considered a
stockholder of the Company at the time of the Award except as otherwise provided
in the applicable Award.

     (c) EFFECTIVE DATE. The Plan shall be effective on the date it is approved
by the stockholders.

     (d) AMENDMENT OF PLAN. The Board may amend, suspend, or terminate the Plan
or any portion thereof at any time, subject to such stockholder approval as the
Board determines to be necessary or advisable.

     (e) GOVERNING LAW. The provisions of the Plan shall be governed by and
interpreted in accordance with the laws of the State of Delaware.

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