EXHIBIT 10.3

1.   As adopted by the Board of Directors on May 11, 1993 and approved by the
     stockholders on June 25, 1993.

2.   As amended by the Board of Directors on March 3, 1997, and approved by the
     stockholders on May 28, 1997.

3.   As amended by the Board of Directors on May 28, 1997 (no stockholder
     approval required).

4.   As amended by the Board of Directors on March 4, 1998 and approved by the
     stockholders on May 27, 1998.

                         GENZYME TRANSGENICS CORPORATION

                         1993 Director Stock Option Plan

         The purpose of this 1993 Director Stock Option Plan (the "Plan") of
Genzyme Transgenics Corporation (the "Company") is to attract and retain highly
qualified non-employee directors of the Company and to encourage ownership of
stock of the Company by such Directors so as to provide additional incentives to
promote the success of the Company.

1.  Administration of the Plan.

         Grants of stock options under the Plan shall be automatic as provided
in Section 6. However, all questions of interpretation with respect to the Plan
and options granted under it shall be determined by the Board of Directors of
the Company (the "Board") or by a committee consisting of one or more directors
appointed by the Board and such determination shall be final and binding upon
all persons having an interest in the Plan.

2. Persons Eligible to Participate in the Plan.

         All directors of the Company who are not employees of the Company or of
any subsidiary of the Company shall be eligible to participate in the Plan,
unless such director irrevocably elects not to participate on or after May 29,
1997.

3.  Shares Subject to the Plan.

         (a) The aggregate number of shares of the Company's Common Stock which
may be optioned under this Plan is 200,000 shares. Shares issued under the Plan
may consist in whole or in part of authorized but unissued shares or treasury
shares.

         (b) In the event of a stock dividend, split-up, combination or
reclassification of shares, recapitalization or other similar capital change
relating to the Company's Common Stock, the maximum aggregate number and kind of
shares or securities of the Company as to which options may be granted under
this Plan and as to which options then outstanding shall be exercisable, and the
option price of such options shall be appropriately adjusted so that the
proportionate number of shares or other securities as to which options may be
granted and the proportionate interest of holders of outstanding options shall
be maintained as before the occurrence of such event.


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         (c) In the event of a consolidation or merger of the Company with
another corporation where the Company's stockholders do not own a majority in
interest of the surviving or resulting corporation, or the sale or exchange of
all or substantially all of the assets of the Company, or a reorganization or
liquidation of the Company, any deferred exercise period shall be automatically
accelerated and each holder of an outstanding option shall be entitled to
receive upon exercise and payment in accordance with the terms of the option the
same shares, securities or property as he would have been entitled to receive
upon the occurrence of such event if he had been, immediately prior to such
event, the holder of the number of shares of Common Stock purchasable under his
or her option; provided, however, that in lieu of the foregoing the Board may
upon written notice to each holder of an outstanding option or right under the
Plan, provide that such option or right shall terminate on a date not less than
20 days after the date of such notice unless theretofore exercised.

         (d) Whenever options under this Plan lapse or terminate or otherwise
become unexercisable the shares of Common Stock which were subject to such
options may again be subjected to options under this Plan. The Company shall at
all times while this Plan is in force reserve such number of shares of Common
Stock as will be sufficient to satisfy the requirements of this Plan.

4.  Non-Statutory Stock Options.

         All options granted under this Plan shall be non-statutory options not
entitled to special tax treatment under Section 422 of the Internal Revenue Code
of 1986, as amended (the "Code").

5.  Form of Options.

         Options granted hereunder shall be in such form as the Board or any
committee appointed pursuant to Section 1 above may from time to time determine.

6.  Grant of Options and Option Terms.

         (a) Automatic Grant of Options. Upon the election or re-election of an
eligible director under this Plan, such director shall automatically be granted
an option to purchase 5,000 shares of Common Stock for each year of the term of
office to which he or she is elected. If such director is elected on a date
other than the date of an annual meeting of stockholders (whether elected by the
Board or the stockholders and whether to fill a vacancy or otherwise), such
director shall automatically be granted options to purchase 5,000 shares of
Common Stock for each year or portion thereof of the term of office to which he
or she is elected. At the 1998 annual meeting of stockholders, any eligible
director who is not being elected or re-elected at such annual meeting shall
automatically be granted an option to purchase 3,000 shares of Common Stock for
each year in such director's remaining term of office. No options shall be
granted hereunder after ten years from the date on which this Plan was initially
approved and adopted by the Board.


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         (b) Date of Grant. The "Date of Grant" for options granted under this
Plan shall be the date of election or re-election as a director or in certain
cases, the 1998 annual meeting of stockholders, as the case may be.

         (c) Option Price. The option price for each option granted under this
Plan shall be the current fair market value of a share of Common Stock of the
Company as determined (i) prior to date on which the Company becomes subject to
the Securities Exchange Act of 1934, as amended (the "Exchange Act"), by the
Board in good faith or in the manner established by the Board from time to time,
and (ii) on or after the date on which the Company is subject to the Exchange
Act, by the last sale price for the Company's Common Stock as reported by the
National Association of Securities Dealers Automated Quotations National Market
System for the business day immediately preceding the Date of Grant.

         (d) Term of Option. The term of each option granted under this Plan
shall be ten years from the Date of Grant.

         (e) Exercisability of Options. Options granted under this Plan to a
director on election or re-election shall become exercisable with respect to
5,000 shares on the Date of Grant and on each annual meeting of stockholders of
the Company following the Date of Grant if and only if the option holder is a
member of the Board at the opening of business on that date (e.g., an option to
purchase 15,000 shares of Common Stock granted at the 1998 annual meeting would
become exercisable with respect to 5,000 shares at each of the 1998, 1999 and
2000 annual meetings). Options granted at the 1998 annual meeting of
stockholders to directors not being elected or re-elected at such meeting shall
become exercisable with respect to 3,000 shares on the Date of Grant and with
respect to grants for 6,000 shares, also on the 1999 annual meeting of
stockholders of the Company, if and only if the option holder is a member of the
Board at the opening of business on that date.

         (f) General Exercise Terms. Directors holding exercisable options under
this Plan who cease to serve as members of the Board may, during their lifetime,
exercise the rights they had under such options at the time they ceased being a
director for the full unexpired term of such option. Any rights that have not
yet become exercisable shall terminate upon cessation of membership on the
Board. Upon the death of a director, those entitled to do so shall have the
right, at any time within twelve months after the date of death, to exercise in
whole or in part any rights which were available to the director at the time of
his or her death. The rights of the option holder may be exercised by the
holder's guardian or legal representative in the case of disability and by the
beneficiary designated by the holder in writing delivered to the Company or, if
none has been designated, by the holder's estate or his or her transferee on
death in accordance with this Plan, in the case of death. Options granted under
the Plan shall terminate, and no rights thereunder may be exercised, after the
expiration of the applicable exercise period. Notwithstanding the foregoing
provisions of this section, no rights under any options may be exercised after
the expiration of ten years from their Date of Grant.

         (g) Method of Exercise and Payment. Options may be exercised only by
written notice to the Company at its head office accompanied by payment of the
full option price for the shares of Common Stock as to which they are exercised.
The option price shall be paid in cash or by check or in shares of Common Stock
of the Company, or in any combination thereof. Shares of 



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Common Stock surrendered in payment of the option price shall have been held by
the person exercising the option for at least six months, unless otherwise
permitted by the Board. The value of shares delivered in payment of the option
price shall be their fair market value, as determined in accordance with Section
6(c) above, as of the date of exercise. Upon receipt of such notice and payment,
the Company shall promptly issue and deliver to the optionee (or other person
entitled to exercise the option) a certificate or certificates for the number of
shares as to which the exercise is made.

         (h) Limitations on Transferability. Options granted under this Plan
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
the Board or any committee appointed by the Board may in its discretion waive
such restriction in any case.

7.  Limitation of Rights.

         (a) No Right to Continue as a Director. Neither the Plan, nor the
granting of an option or any other action taken pursuant to the Plan, shall
constitute an agreement or understanding, express or implied, that the Company
will retain an option holder as a director for any period of time or at any
particular rate of compensation.

         (b) No Stockholders' Rights for Options. A director shall have no
rights as a stockholder with respect to the shares covered by options until the
date the director exercises such options and pays the option price to the
Company, and no adjustment will be made for dividends or other rights for which
the record date is prior to the date such option is exercised and paid for.

8.  Amendment or Termination.

         The Board may amend or terminate this Plan at any time. The Board may
amend or modify any outstanding option in any respect, provided that the
optionee's consent to such action shall be required unless the Board determines
that the action, taking into account any relative action, would not materially
and adversely affect the optionee.

9.  Stockholder Approval.

         This Plan was approved by the Stockholders on June 25, 1993 and the
amendments approved by the Board of Directors on March 3, 1997 and any further
amendments hereto shall be subject to stockholder approval to the extent (i)
required by law, (ii) required by Nasdaq or stock exchange listing requirements,
as determined by the Board of Directors, or (iii) as desirable, as determined by
the Board of Directors, to comply with Rule 16b-3 under the Securities Exchange
Act of 1934, as amended. In the event any approval is not obtained, all options
granted under this Plan after such further amendment shall be void and without
effect.

10.  Governing Law.

         This Plan shall be governed by and interpreted in accordance with the
laws of the Commonwealth of Massachusetts.


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