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                                                          EXHIBIT 10.8

    1. Adopted by the Board of Directors on May 1, 1993; Approved by the
stockholders on June 25, 1993.

    2. Amended by the Board of Directors on September 24, 1993 (No stockholder
approval required).

    3. Amended by the Board of Directors on October 24, 1994, March 17, 1995 and
April 6, 1995; Approved by the stockholders on May 19, 1995.

    4. Amended by the Board of Directors on March 13, 1996; Approved by the
stockholders on May 15, 1996.

    5. Amended by the Board of Directors on March 3, 1997 (No stockholder
approval required).

                        GENZYME TRANSGENICS CORPORATION

    1993 Equity Incentive Plan

    Section 1. Purpose

    The purpose of the Genzyme Transgenics Corporation 1993 Equity Incentive
Plan (the "Plan") is to attract and retain key employees and consultants to
provide an incentive for them to assist the Company to achieve long-range
performance goals, and to enable them to participate in the long-term growth of
the Company.

    Section 2. Definitions

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

    "Award" means any Option, Stock Appreciation Right, Performance Share,
Restricted Stock or Stock Unit awarded 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.

    "Committee" means either any one of one or more committees of the Board
appointed by the Board to administer the Plan, the members of which are
"Non-Employee Directors" within the meaning of Rule 16b-3 under the Securities
Exchange Act of 1934, as amended, or any successor provision (the "Rule") to the
extent necessary to comply with the Rule.

    "Common Stock" or "Stock" means the Common Stock, $0.01 par value, of the
Company.
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    "Company" means Genzyme Transgenics Corporation.

    "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
shall mean the Participant's estate.

    "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.

    "Incentive Stock Option" means an option to purchase shares of Common Stock
awarded to a Participant under Section 6 which is intended to meet the
requirements of Section 422 of the Code or any successor provision.


    "Nonstatutory Stock Option" means an option to purchase shares of Common
Stock awarded to a Participant under Section 6 which is not intended to be an
Incentive Stock Option.

    "Option" means an Incentive Stock Option or a Nonstatutory Stock Option.

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

    "Performance Cycle" or "Cycle" means the period of time selected by the
Committee during which performance is measured for the purpose of determining
the extent to which an award of Performance Shares has been earned.

    "Performance Shares" mean shares of Common Stock which may be earned by the
achievement of performance goals awarded to a Participant under Section 8.

    "Reporting Person" means a person subject to Section 16 of the Securities
Exchange Act of 1934 or any successor provision.

    "Restricted Period" means the period of time selected by the Committee
during which an award of Restricted Stock may be forfeited to the Company.

    "Restricted Stock" means shares of Common Stock subject to forfeiture
awarded to a Participant under Section 9.

    "Stock Appreciation Right" or "SAR" means a right to receive any excess in
value of shares of Common Stock over the exercise price awarded to a Participant
under Section 7.

    "Stock Unit" means an award of Common Stock or units that are valued in
whole or in part by reference to, or otherwise based on, the value of Common
Stock, awarded to a Participant under Section 10.
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    Section 3. Administration

    The Plan shall be administered by the Committee.  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 and all
determinations under the Plan with respect thereto, provided that the Committee
shall fix the maximum amount of such Awards for the group and a maximum for any
one Participant.

    Section 4. Eligibility

    All employees, and in the case of Awards other than Incentive Stock Options,
consultants of the Company or any Affiliate capable of contributing
significantly to the successful performance of the Company, other than a person
who has irrevocably elected not to be eligible, are eligible to be Participants
in the Plan.

    Section 5. Stock Available for Awards

    (a) Subject to adjustment under subsection (b), Awards may 1 be made
under the Plan for up to 2,515,000 shares of Common Stock. If any Award in
respect of shares of Common Stock expires or is terminated unexercised or is
forfeited for any reason or settled in a manner that results in fewer shares
outstanding than were initially awarded, including without limitation the
surrender of shares in payment for the Award or any tax obligation thereon,
the shares subject to such Award or so surrendered, as the case may be, to
the extent of such expiration, termination, forfeiture or decrease, shall
again be available for award under the Plan, subject, however, in the case of
Incentive Stock Options, to any limitation required under the Code. 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 in whole or in part
of authorized but unissued shares or treasury shares.

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(1) This number includes 224,350 shares reserved for issuance upon the exercise
    of outstanding options to purchase shares of common stock of TSI
    Corporation, which options were assumed by the Company in October 1994 in
    connection with the Company's acquisition of TSI Corporation.

    (b) In the event that the Committee determines that any stock dividend,
extraordinary cash dividend, creation of a class of equity securities,
recapitalization, reorganization, merger, consolidation, split-up, spin-off,
combination, exchange of shares, warrants or rights offering to purchase
Common Stock at a price substantially below fair market value, or other
similar transaction affects the Common Stock such that an adjustment

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is required in order to preserve the benefits or potential benefits intended
to be made available under 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 award, exercise or
conversion price with respect to any of the foregoing, and if considered
appropriate, the Committee may make provision for a cash payment with respect
to an outstanding Award, provided that the number of shares subject to any
Award shall always be a whole number.

    Section 6. Stock Options

    (a) Subject to the provisions of the Plan, the Committee may award Incentive
Stock Options and Nonstatutory Stock Options and determine the number of shares
to be covered by each Option, the option price therefor and the conditions and
limitations applicable to the exercise of the Option. The terms and conditions
of Incentive Stock Options shall be subject to and comply with Section 422 of
the Code, or any successor provision, and any regulations thereunder.

    (b) The Committee shall establish the option price at the time each Option
is awarded, which price shall not be less than 100% of the Fair Market Value of
the Common Stock on the date of award.

    (c) Each Option shall be exercisable at such times and subject to such terms
and conditions as the Committee may specify in the applicable Award 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.

    (d) No shares shall be delivered pursuant to any exercise of an Option until
payment in full of the option 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 award of the Option, by delivery of a note or
shares of Common Stock owned by the optionee, including Restricted Stock, valued
at their Fair Market Value on the date of delivery, or such other lawful
consideration as the Committee may determine.

    (e) The Committee may provide for the automatic award of an Option upon the
delivery of shares to the Company in payment of an Option for up to the number
of shares so delivered.

    Section 7. Stock Appreciation Rights

    (a) Subject to the provisions of the Plan, the Committee may award SARs in
tandem with an Option (at or after the award of the Option), or alone and
unrelated to an Option. SARs in tandem with an Option shall terminate to the
extent that the related Option is exercised, and the related Option shall
terminate to the extent that the tandem SARs are

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exercised. SARs shall have an exercise price of not less than the Fair Market
Value of the Common Stock on the date of award, or in the case of SARs in
tandem with Options, the exercise price of the related Option.

    (b) An SAR related to an Option which can only be exercised during limited
periods following a change in control of the Company, may entitle the
Participant to receive an amount based upon the highest price paid or offered
for Common Stock in any transaction relating to the change in control or paid
during the thirty-day period immediately preceding the occurrence of the change
in control in any transaction reported in the stock market in which the Common
Stock is normally traded.

    Section 8. Performance Shares

    (a) Subject to the provisions of the Plan, the Committee may award
Performance Shares and determine the number of such shares for each Performance
Cycle and the duration of each Performance Cycle. There may be more than one
Performance Cycle in existence at any one time, and the duration of Performance
Cycles may differ from each other. The payment value of Performance Shares shall
be equal to the Fair Market Value of the Common Stock on the date the
Performance Shares are earned or, in the discretion of the Committee, on the
date the Committee determines that the Performance Shares have been earned.

    (b) The Committee shall establish performance goals for each Cycle, for the
purpose of determining the extent to which Performance Shares awarded for such
Cycle are earned, on the basis of such criteria and to accomplish such
objectives as the Committee may from time to time select. During any Cycle, the
Committee may adjust the performance goals for such Cycle as it deems equitable
in recognition of unusual or non-recurring events affecting the Company, changes
in applicable tax laws or accounting principles, or such other factors as the
Committee may determine.

    (c) As soon as practicable after the end of a Performance Cycle, the
Committee shall determine the number of Performance Shares which have been
earned on the basis of performance in relation to the established performance
goals. The payment values of earned Performance Shares shall be distributed to
the Participant or, if the Participant has died, to the Participant's Designated
Beneficiary, as soon as practicable thereafter. The Committee shall determine,
at or after the time of award, whether payment values will be settled in whole
or in part in cash or other property, including Common Stock or Awards.

    Section 9. Restricted Stock

    (a) Subject to the provisions of the Plan, the Committee may award shares of
Restricted Stock and determine the duration of 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 shall be issued for no cash consideration or such minimum consideration as
may be required by applicable law.
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    (b) 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.

    Section 10. Stock Units

    (a) Subject to the provisions of the Plan, the Committee may award Stock
Units subject to such terms, restrictions, conditions, performance criteria,
vesting requirements and payment rules as the Committee shall determine.

    (b) Shares of Common Stock awarded in connection with a Stock Unit Award
shall be issued for no cash consideration or such minimum consideration as may
be required by applicable law.

    Section 11. General Provisions Applicable to Awards

   (a) Limitations on Transferability. Options shall not be transferable by the
recipient other than by will or the laws of descent and distribution and are
exercisable during such person's lifetime only by such person or by such
person's guardian or legal representative; provided that the Committee may in
its discretion waive such restriction in any case.

    (b) Documentation. Each Award under the Plan shall be evidenced by a writing
delivered to 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 comply with applicable tax and regulatory laws and
accounting principles.

    (c) Committee Discretion. Each type of Award may be made alone, in addition
to or in relation to any other type of Award. The terms of each type of Award
need not be identical, and the 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 award or at any time thereafter.

    (d) Settlement. The Committee shall determine whether Awards are settled in
whole or in part in cash, Common Stock, other securities of the Company, Awards
or other property. The Committee may permit a Participant to defer all or any
portion of a payment under the Plan, including the crediting of interest on
deferred amounts denominated in cash and dividend equivalents on amounts
denominated in Common Stock.
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    (e) 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 currently or deferred with or without interest, and (ii)
cash payments in lieu of or in addition to an Award.

    (f) Termination of Employment. The Committee shall determine the effect on
an Award of the disability, death, retirement or other termination of employment
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.

    (g) 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, 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 realization of the Award, (ii) provide for
the purchase of the Award upon the Participant's request for an amount of cash
or other property that could have been received upon the exercise or realization
of the Award had the Award been currently exercisable or payable, (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 and in the best interests of the Company.

    (h) Withholding. 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 Options 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 otherwise due to the Participant. In the Committee's discretion, the
Participant may pay any taxes due with respect to an Option in whole or in part
in shares of Common Stock, including shares retained from the Option creating
the tax obligation, valued at their Fair Market Value on the date of retention
or delivery.

    (i) 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 comply with applicable laws.

    (j) 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, provided that the
Participant's consent to such action shall be required unless the Committee
determines that the action, taking into account any related action, would not
materially and adversely affect the Participant.
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    Section 12. Miscellaneous

    (a) Limitation on Number of Shares Granted. Notwithstanding any other
provision of the Plan, the aggregate number of shares of Common Stock subject to
Options and SARs that may be granted within any fiscal year to any one Eligible
Person under the Plan shall not exceed that number of shares equal to 20% of the
total number of shares reserved for issuance under the Plan, except for grants
to new hires during the fiscal year of hiring which shall not exceed that number
of shares equal to 30% of the total number of shares reserved for issuance under
the Plan.

    (b) No Right To Employment. No person shall have any claim or right to be
granted an Award, and the grant of an Award shall not be construed as giving a
Participant the right to continued employment. The Company expressly reserves
the right at any time to dismiss a Participant free from any liability or claim
under the Plan, except as expressly provided in the applicable Award.

    (c) No Rights As Shareholder. Subject to the provisions of the applicable
Award, no Participant or Designated Beneficiary shall have any rights as a
shareholder with respect to any shares of Common Stock to be distributed under
the Plan until he or she becomes the holder thereof. A Participant to whom
Common Stock is awarded shall be considered the holder of the Stock at the time
of the Award except as otherwise provided in the applicable Award.

    (d) Effective Date. Subject to the approval of the shareholders of the
Company, the Plan shall be effective on May 1, 1993. Prior to such approval,
Awards may be made under the Plan expressly subject to such approval.

    (e) Amendment of Plan. The Board may amend, suspend or terminate the Plan or
any portion thereof at any time, provided that no amendment shall be made
without shareholder approval if such approval is necessary to comply with any
applicable tax or regulatory requirement.

    (f) Governing Law. The provisions of the Plan shall be governed by and
interpreted in accordance with the laws of the Commonwealth of Massachusetts.
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