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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   ----------

                                   FORM 10-K/A

                  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

FOR THE FISCAL YEAR ENDED DECEMBER 31, 1995          COMMISSION FILE NO. 0-14680

                               GENZYME CORPORATION
             (Exact name of Registrant as specified in its charter)

        MASSACHUSETTS                                    06-1047163
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
 incorporation or organization)

         ONE KENDALL SQUARE                                        02139
       CAMBRIDGE, MASSACHUSETTS                                 (Zip Code)
(Address of principal executive offices)

                                 (617) 252-7500
              (Registrant's telephone number, including area code)

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           Securities registered pursuant to Section 12(b) of the Act:
                                      NONE

           Securities registered pursuant to Section 12(g) of the Act:
    GENERAL DIVISION COMMON STOCK, $0.01 PAR VALUE ("GENERAL DIVISION STOCK")
        TISSUE REPAIR DIVISION COMMON STOCK, $0.01 PAR VALUE ("TR STOCK")
                     GENERAL DIVISION STOCK PURCHASE RIGHTS
                            TR STOCK PURCHASE RIGHTS
 WARRANTS (DATED NOVEMBER 3 AND 10, 1989) TO PURCHASE GENERAL DIVISION STOCK AND
                                    TR STOCK
SERIES N WARRANTS (DATED MAY 5, 1992) TO PURCHASE GENERAL DIVISION STOCK AND TR
                                      STOCK

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         Indicate by check mark whether the Registrant: (1) has filed all
reports required to be filed by Section 13 or 15(d) of the Securities Exchange
Act of 1934 during the preceding twelve months (or for such shorter period that
the Registrant was required to file such reports), and (2) has been subject to
such filing requirements for the past 90 days. Yes  X  No
                                                   ---    ---

         Indicate by check mark if disclosure of delinquent filers pursuant to
Item 405 of Regulation S-K is not contained herein, and will not be contained,
to the best of Registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K. [ ]

         Aggregate market value of voting stock held by non-affiliates of the
Registrant as of March 1, 1996: $2,349,667,466

         Number of shares of the Registrant's General Division Stock outstanding
as of March 1, 1996: 31,844,070

         Number of shares of the Registrant's TR Stock outstanding as of March
1, 1996: 12,110,503

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                       DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Registrant's Proxy Statement for the Annual Meeting of
Stockholders to be held May 16, 1996 were incorporated by reference into Part
III of the Registrant's Form 10-K amended hereby.

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This report on Form 10-K/A constitutes Amendment No. 1 to the registrant's Form 
10-K for the year ended December 31, 1995. Item 14 is hereby amended as follow:

- - Exhibit 23.1, Consent of Coopers & Lybrand L.L.P., is revised to include
consent to the incorporation  by reference in the registration statements of 
Genzyme Corporation on Form S-4 (File Nos. 333-01105, 333-02357 and 333-02947)
of their reports dated March 1, 1996, except as to Note O which is dated March
26, 1996 of their audits of the consolidated financial statements and financial
statemet schedule of the Genzyme Corporation and Subsidiaries, dated March 1,
1996 except as to Note R which is March 26, 1996 on our audits of the combined
financial statements and financial statement schedule of Genzyme General
Division and dated March 1, 1996 except as to Note O which is March 26, 1996
on our audits of the combined financial statements and financial statement 
schedule of Genzyme Tissue Repair Division all as of December 31, 1994 and 1995 
and for each of the  three years in the period ended December 31, 1995, which 
reports are include in the registrant's 1995 Annual Report on Form 10-K.

- - Exhibit 23.2, Consent of Coopers & Lybrand L.L.P., relating to the Annual
Report of Genzyme Corporation Retirement Savings Plan (the "Plan"), is filed
herewith.

- - Exhibit 99.1, which includes information, financial statements and exhibits
required by Form 11-K related to the Plan, is filed herewith.





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                                     PART IV

ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(A)  1. FINANCIAL STATEMENTS

     The financial statements are listed under Part II, Item 8 of this Report.

     2. FINANCIAL STATEMENT SCHEDULES

     The financial statement schedules are listed under Part II, Item 8 of this
     Report.

     3. EXHIBITS

     The exhibits are listed below under Part IV, Item 14(c) of this report.

(B)  REPORTS ON FORM 8-K

     Reports on Form 8-K were filed with the Commission during the fourth
     quarter of 1995 to report the following items as of the dates indicated:

     - Genzyme filed a report on Form 8-K dated October 12, 1995 reporting under
     Item 5 of Form 8-K the acquisition of its majority-owned subsidiary, IG
     Laboratories, Inc. ("IG Labs") in a transaction in which IG Labs was merged
     with and into Genzyme. The report incorporated by reference the contents of
     Genzyme's press release dated September 29, 1995.

(C)  EXHIBITS

EXHIBIT                            DESCRIPTION
  NO.                              -----------
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*3.1    -    Articles of Organization of Genzyme. Filed as Exhibit 3.1 to
             Genzyme's Form 10-K for 1994.

*3.2    -    By-laws of Genzyme. Filed as Exhibit 3.2 to Genzyme's Form 8-K
             dated December 31, 1991.

*4.1    -    Amended and Restated Rights Agreement, dated as of October 13,
             1994 between Genzyme and American Stock Transfer and Trust Company.
             Filed as Exhibit 4 to Genzyme's Form 8-K dated December 29, 1994.

*4.2    -    Indenture dated as of October 11, 1991 between Genzyme and State
             Street Bank and Trust Company. Filed as Exhibit 4.1 to Genzyme's
             Form 8-K dated October 11, 1991.

*4.3    -    First Supplement dated as of December 20, 1991 to Indenture dated
             as of October 11, 1991 between Genzyme and State Street Bank and
             Trust Company. Filed as Exhibit 4.1 to Genzyme's Form 8-K dated
             December 31, 1991.

*4.4    -    Global Note of Genzyme in the principal amount of $100,000,000
             dated October 11, 1991, payable to Cede and Co., as nominee for The
             Depository Trust Company. Filed as Exhibit 4.2 to Genzyme's Form
             8-K dated October 11, 1991.

*4.5    -    Specimen Warrant to purchase Genzyme Common Stock issued to
             limited partners of Genzyme Development Partners, L.P. on November
             3, 1989. Filed as Exhibit 4.3 to Genzyme's Form 10-K for 1990.

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EXHIBIT                            DESCRIPTION
  NO.                              -----------
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*4.6    -    Specimen Warrant to purchase Genzyme Common Stock issued to
             limited partners of Genzyme Development Partners, L.P. on November
             10, 1989. Filed as Exhibit 4.4 to Genzyme's Form 10-K for 1990.

*4.7    -    Specimen Warrant to purchase Genzyme Common Stock issued to Paine
             Webber Development Company on November 10, 1989. Filed as Exhibit
             4.5 to Genzyme's Form 10-K for 1990.

*4.8    -    Specimen Series N Warrant to purchase Genzyme Common Stock issued
             to shareholders of Neozyme II Corporation ("Neozyme II"). Filed as
             Exhibit 28.5 to Genzyme's Form 10-Q for March 31, 1992.

*4.9    -    Specimen Callable Warrant to purchase Genzyme Common Stock issued
             to shareholders of Neozyme II. Filed as Exhibit 28.6 to Genzyme's
             Form 10-Q for March 31, 1992.

*10.1   -    Leases by Whatman Reeve Angel Limited to Whatman Biochemicals
             Limited dated May 1, 1981. Filed as Exhibit 10.12 to Genzyme's
             Registration Statement on Form S-1, File No. 33-4904.

*10.2   -    Lease dated as of September 15, 1989 for 95-111 Binney Street,
             Cambridge, Massachusetts between Genzyme and the Trustees of the
             Cambridge East Trust. Filed as Exhibit 10.2 to Genzyme's Form 10-K
             for 1992. First amendment of lease dated February 28, 1994. Filed
             as Exhibit 10.2 to Genzyme's Form 10-K for 1993.

*10.3   -    Lease dated December 20, 1988 for Building 1400, One Kendall
             Square, Cambridge, Massachusetts between Genzyme and the Trustees
             of Old Binney Realty Trust, as amended by letters dated December
             20, 1988, January 19, 1989 and January 31, 1989. Filed as Exhibit
             10.18 to Genzyme's Form 10-K for 1988. Addendum dated September 20,
             1991 to Lease for Building 1400, One Kendall Square, Cambridge,
             Massachusetts. Filed as Exhibit 19.1 to Genzyme's Form 10-Q dated
             September 30, 1991. Addenda dated August 2, 1990 and April 6, 1993
             to Lease for Building 1400, One Kendall Square, Cambridge,
             Massachusetts. Filed as Exhibit 10.3 to Genzyme's Form 10-K for
             1993.

*10.4   -    Lease dated December 20, 1988 for Building 700, One Kendall
             Square, Cambridge, Massachusetts between Genzyme and Trustees of
             Old Kendall Realty Trust, as amended by letters dated December 20,
             1988 and January 31, 1989. Filed as Exhibit 10.19 to Genzyme's Form
             10-K for 1988.

*10.5   -    Lease dated September 30, 1985 for 51 New York Avenue,
             Framingham, Massachusetts. Filed as Exhibit 10.8 to Genzyme's Form
             10-K for 1990. Amendment No. 1, dated October 11, 1990, and
             Amendment No. 2, dated May 12, 1993, to lease for 51 New York
             Avenue, Framingham, Massachusetts. Filed as Exhibit 10.5 to
             Genzyme's Form 10-K for 1993.

*10.6   -    Lease dated April 30, 1990 for 64 Sidney Street, Cambridge,
             Massachusetts between BioSurface Technology, Inc. ("BioSurface")
             and Forest City 64 Sidney Street, Inc. Filed as Exhibit 10.22 to
             the Registration Statement of BioSurface on Form S-1, File No.
             33-55874.

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EXHIBIT                            DESCRIPTION
  NO.                              -----------
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*10.7   -    Sublease Lease dated May 22, 1992 for three buildings at 74-84
             New York Avenue, Framingham, Massachusetts between Genzyme and
             Prime Computer, Inc. Filed as Exhibit 10.7 to Genzyme's Form 10-K
             for 1993.

*10.8   -    Lease dated May 22, 1992 for three buildings at 74-84 New York
             Avenue, Framingham, Massachusetts between Genzyme and Mark L. Fins,
             David J. Winstanley and Bruce A. Gurall, tenants in common. Filed
             as Exhibit 10.8 to Genzyme's Form 10-K for 1993.

*10.9   -    Lease dated June 1, 1992 for land at Allston Landing, Allston,
             Massachusetts between Allston Landing Limited Partnership and the
             Massachusetts Turnpike Authority. Filed as Exhibit 10.9 to
             Genzyme's Form 10-K for 1993.

*10.10  -    Underlease for Block 13 building at Kings Hill Business Park West
             Malling Kent among Rouse and Associates Block 13 Limited, Genzyme
             (UK) Limited and Genzyme Corporation. Filed as Exhibit 10.11 to
             Genzyme's Registration Statement on Form 8-B dated December 31,
             1991, filed on March 2, 1992.

*10.11  -    Agreement of Limited Partnership dated as of September 13, 1989
             between Genzyme Development Corporation II, as General Partner, and
             each of the Limited Partners named therein. Filed as Exhibit 10(aa)
             to Genzyme's Registration Statement on Form S-4, File No. 33-32343.

*10.12  -    Cross License Agreement dated as of September 13, 1989 between
             Genzyme Corporation and Genzyme Development Partners, L.P. Filed as
             Exhibit 10(bb) to Genzyme's Registration Statement on Form S-4,
             File No. 33-32343.

*10.13  -    Development Agreement dated as of September 13, 1989 between
             Genzyme Corporation and Genzyme Development Partners, L.P. Filed as
             Exhibit 10(cc) to Genzyme's Registration Statement on Form S-4,
             File No. 33-32343.

*10.14  -    Amendment No. 1 dated January 4, 1994 to Development Agreement
             dated as of September 13, 1989 between Genzyme and Genzyme
             Development Partners, L.P. Filed as Exhibit 10.14 to Genzyme's Form
             10-K for 1993.

*10.15  -    Notice dated January 4, 1994 from Genzyme to Genzyme Development
             Partners, L.P. Filed as Exhibit 10.15 to Genzyme's Form 10-K for
             1993.

*10.16  -    Notice dated January 13, 1995 from Genzyme to Genzyme Development
             Partners, L.P. Filed as Exhibit 10.16 to Genzyme's Form 10-K for
             1994.

*10.17  -    Notice dated February 22, 1996 from Genzyme to Genzyme
             Development Partners, L.P. Filed as Exhibit 10.17 to Genzyme's Form
             10-K for 1995.

*10.18  -    Partnership Purchase Option Agreement dated as of September 13,
             1989 between Genzyme Corporation, Genzyme Development Corporation
             II, Genzyme Development Partners, L.P. each Class A Limited Partner
             and the Class B Limited Partner. Filed as Exhibit 10(dd) to
             Genzyme's Registration Statement on Form S-4, File No. 33-32343.

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EXHIBIT                            DESCRIPTION
  NO.                              -----------
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*10.19   -   Partnership Purchase Agreement, undated and unexecuted, between
             Genzyme Corporation, Genzyme Development Corporation II, Genzyme
             Development Partners, L.P., each Class A Limited Partner and the
             Class B Limited Partner, as the case may be. Filed as Exhibit
             10(ee) to Genzyme's Registration Statement on Form S-4, File No.
             33-32343.

*10.20   -   Joint Venture Agreement dated as of September 13, 1989 between
             Genzyme Corporation and Genzyme Development Partners, L.P. Filed as
             Exhibit 10(ff) to Genzyme's Registration Statement on Form S-4,
             File No. 33-32343.

*10.21   -   Technology License and Supply Agreement dated as of September 8,
             1989 between Imedex and Genzyme. Filed as Exhibit 10.30 to
             Genzyme's Form 10-K for 1990.**

*10.22   -   1988 Director Stock Option Plan. Filed as Annex VIII to Genzyme's
             Registration Statement on Form S-4, File No. 33-83346.

*10.23   -   1990 Equity Incentive Plan. Filed as Annex VII to Genzyme's
             Registration Statement on Form S-4, File No. 33-83346.

*10.24   -   1990 Employee Stock Purchase Plan. Filed as Annex IX to Genzyme's
             Registration Statement on Form S-4, File No. 33-83346.

*10.25   -   Executive Employment Agreement dated as of January 1, 1990
             between Genzyme and Henri A. Termeer. Filed as Exhibit 10.32 to
             Genzyme's Form 10-K for 1990.

*10.26   -   Form of Severance Agreement between Genzyme and certain senior
             executives, together with schedule identifying the provisions
             applicable to each executive. Filed as Exhibit 10.33 to Genzyme's
             Form 10-K for 1990. Schedule identifying executives currently party
             to such Severance Agreement filed as Exhibit 10.32 to Genzyme's
             Form 10-K for 1993.

*10.27   -   Form of Indemnification Agreement between Genzyme and certain
             senior executives, together with schedule identifying the
             provisions applicable to each executive. Filed as Exhibit 10.34 to
             Genzyme's Form 10-K for 1990. Schedule identifying executives
             currently party to such Indemnification Agreement filed as Exhibit
             10.33 to Genzyme's Form 10-K for 1993.

*10.28   -   Consulting Agreement dated March 1, 1993 between Genzyme and
             Henry E. Blair. Filed as Exhibit 10.29 to Genzyme's 10-K for 1992.
             Consulting Agreement dated February 3, 1994 between Genzyme and
             Henry E. Blair. Filed as Exhibit 10.35 to Genzyme's Form 10-K for
             1993.

*10.29   -   Technology License Agreement dated April 28, 1992 between Genzyme
             and Neozyme II. Filed as Exhibit 28.7 to Genzyme's Form 10-Q for
             March 31, 1992.

*10.30   -   Research and Development Agreement dated April 28, 1992 between
             Genzyme and Neozyme II. Filed as Exhibit 28.8 to Genzyme's Form
             10-Q for March 31, 1992.

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EXHIBIT                            DESCRIPTION
  NO.                              -----------
- -------

*10.31      -     Purchase Option  Agreement  dated April 28, 1992 among 
                  Genzyme, PaineWebber Incorporated, Shearson Lehman Brothers,
                  Inc., Cowen & Company, PaineWebber International (U.K.) Ltd.,
                  and Lehman Brothers International Limited. Filed as Exhibit
                  28.9 to Genzyme's Form 10-Q for March 31, 1992.

*10.32      -     Administrative  Agreement dated April 28, 1992 between Genzyme
                  and Neozyme II. Filed as Exhibit 28.10 to Genzyme's Form 10-Q
                  for March 31, 1992.

*10.33      -     Series 1992 Note of Neozyme II dated April 28, 1992.  Filed as
                  Exhibit 28.11 to Genzyme's Form 10-Q for March 31, 1992.

*10.34      -     Amendment  No. 1 to  Technology  License  Agreement and 
                  Research and Development Agreement between Genzyme and Neozyme
                  II dated as of August 11, 1993. Filed as Exhibit 10.42 to
                  Genzyme's Form 10-K for 1993.

*10.35      -     Technology Transfer Agreement between Genzyme and Genzyme
                  Transgenics Corporation ("GTC") dated as of May 1, 1993. Filed
                  as Exhibit 2.1 to the Registration Statement on Form S-1 of
                  GTC (File No. 33-62872).

*10.36      -     Research and Development  Agreement between Genzyme and GTC 
                  dated as of May 1, 1993. Filed as Exhibit 10.1 to the
                  Registration Statement on Form S-1 of GTC (File No. 33-62872).

*10.37      -     Services  Agreement  between  Genzyme and GTC dated as of May
                  1, 1993. Filed as Exhibit 10.2 to the Registration Statement
                  on Form S-1 of GTC (File No. 33-62872).

*10.38      -     Series A Convertible  Preferred Stock Purchase Agreement  
                  between Genzyme and GTC dated as of May 1, 1993. Filed as
                  Exhibit 10.5 to the Registration Statement on Form S-1 of GTC
                  (File No. 33-62872).

*10.39      -     Convertible Debt and Development Funding  Agreement dated as 
                  of March 29, 1996 between Genzyme and GTC. Filed as Exhibit
                  10.39 to Genzyme's Form 10-K for 1995.

*10.40      -     Common Stock Purchase Agreement between Argus Pharmaceuticals,
                  Inc. and Genzyme Corporation dated as of September 10, 1993.
                  Filed as Exhibit A to Schedule 13D filed by Genzyme on
                  September 20, 1993.**

*10.41      -     Agreement and Plan of Reorganization dated as of July 25, 
                  1994, as amended, among Genzyme Corporation, Phoenix
                  Acquisition Corporation and BioSurface Technology, Inc. Filed
                  as Annex X to Genzyme's Registration Statement on Form S-4,
                  File No. 33-83346.

*10.42      -     Agreement and Plan of Merger dated as of January 11, 1996 
                  among Genzyme, Genetrix, Inc. and the Principal Stockholders
                  of Genetrix. Filed as Exhibit 2 to Genzyme's Regristration
                  Statement on Form S-4, File No. 333-1105.

*10.43      -     License and Development Agreement between Celtrix 
                  Pharmaceuticals, Inc. ("Celtrix") and Genzyme Corporation
                  dated as of June 24, 1994. Filed as Exhibit 10.42 to Celtrix's
                  Annual Report on Form 10-K for the fiscal year ended March 31,
                  1994.**

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EXHIBIT                            DESCRIPTION
  NO.                              -----------
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*10.44      -     Common Stock Purchase Agreement dated as of June 24, 1994
                  between Celtrix and Genzyme Corporation. Filed as Exhibit A to
                  Schedule 13D filed by Genzyme on July 5, 1994.

*11         -     Computation of weighted  average  shares used in computing per
                  share amounts. Filed as Exhibit 11 to Genzyme's Form 10-K for
                  1995.

*21         -     Subsidiaries of the Registrant.  Filed as Exhibit 21 to 
                  Genzyme's Form 10-K for 1995.

 23.1      -      Consent of Coopers & Lybrand L.L.P.. Filed as Exhibit 23.1 to
                  Genzyme's Form 10-K for 1995. Filed herewith.

 23.2       -     Consent of Coopers & Lybrand L.L.P.  relating to the Annual 
                  Report of Genzyme Corporation Retirement Savings Plan included
                  in Exhibit 99.1 to Genzyme's Form 10-K for 1995. Filed
                  herewith.

*27         -     Financial Data Schedules (for EDGAR filing purposes only).

 99.1       -     Information,  financial  statements  and  exhibits  required 
                  by Form 11-K with respect to the Genzyme Corporation
                  Retirement Savings Plan. Filed herewith.

* Indicates exhibit previously filed with the Securities and Exchange Commission
and incorporated by reference. Exhibits filed with Forms 10-K, 10-Q, 8-K or 8-B
of Genzyme Corporation were filed under Commission File No. 0-14680.

** Confidential treatment has been granted for the deleted portions of Exhibits
10.21, 10.40 and 10.43.

EXECUTIVE COMPENSATION PLANS AND ARRANGEMENTS

         Exhibits 10.22 through 10.28 above are management contracts or
compensatory plans or arrangements in which the executive officers or directors
of Genzyme participate.

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                                   SIGNATURES

         Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned.

                                       GENZYME CORPORATION

Date: June 28, 1996                    By: /s/David J. McLachlan
                                           ------------------------------
                                           David J. McLachlan
                                           Senior Vice President, Finance

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                         GENZYME CORPORATION FORM 10-K/A
                                 Amendment No. 1

                                  Exhibit Index



Exhibit                               Description                                                                  Page
- -------                               -----------                                                                  ----
                                                                                                              
   23.1 -         Consent of Coopers & Lybrand L.L.P. Filed herewith                                                11
  
   23.2 -         Consent of Coopers & Lybrand L.L.P., relating to the                                              12
                  Annual Report of Genzyme Corporation Retirement Savings Plan
                  as reported in Exhibit 99.1 to Genzyme's 1995 Form 10-K/A.
                  Filed herewith.

   99.1 -         Information, financial statements and exhibits required
                  by Form 11-K with respect to the Genzyme Corporation
                  Retirement Savings Plan.  Filed herewith.                                                         13


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