Exhibit 10.16

GENZYME CORPORATION DIRECTORS' DEFERRED  COMPENSATION PLAN

ARTICLE I

GENERAL

1.1Establishment of Plan.Genzyme Corporation ("Genzyme") established the Genzyme Directors' Deferred
Compensation Plan (the "plan"), effective as of May 16, 1996, to allow each member of the Genzyme Board of Directors who is not also an officer or employee of Genzyme or its subsidiaries (an
"outside director") to defer receipt of all or a portion of the cash compensation payable to him or her as such a director of Genzyme until (i) with respect to compensation earned prior to
January 1, 2005, the termination of his or her service as a director, or (ii) with respect to compensation earned on or after January 1, 2005, his or her Termination of Service as
defined in Section 3.8, or (iii) with respect to compensation whenever earned, but subject to the requirements set forth in Section 3.1, such other date
as may be specified by the director. The plan as set forth below was amended and restated effective December 1, 2008.

1.2No Right to Corporate Assets.The plan is unfunded and Genzyme will not be required to set aside, segregate,
or deposit any funds or assets of any kind to meet its obligations hereunder. Nothing in the plan will give a participant, a participant's beneficiary or any other person any equity or other interest
in the assets of Genzyme, or create a trust of any kind or a fiduciary relationship of any kind between Genzyme and any such person. Any rights that a participant, beneficiary or other person may have
under the plan will be solely those of a general unsecured creditor of Genzyme.

1.3Limitation on Rights Created by Plan.Nothing in the plan will give a participant any right to continue as a
director of Genzyme.

1.4Nonalienation of Benefits.The rights and benefits of a participant in the plan are personal to the
participant. No interest, right or claim under the plan and no distribution therefrom will be assignable, transferable or subject to sale, mortgage, pledge, hypothecation, anticipation, garnishment,
attachment, execution or levy, except by designation of beneficiaries as provided in Section 3.5.

1.5Binding Effect of Plan.The plan will be binding upon and inure to the benefit of participants and
designated beneficiaries and their heirs, executors and administrators, and to the benefit of Genzyme and its assigns and successors in interest.

1.6Administration.The plan will be administered by the Secretary of Genzyme, who will have sole responsibility
for its interpretation.

1.7Interpretation.The plan will be construed, enforced and administered according to the laws of the
Commonwealth of Massachusetts.

ARTICLE II

DEFERRAL OF COMPENSATION

2.1Deferral Agreement.Any active outside director (a "participant") is eligible to participate in the plan.
For compensation earned on or after January 1, 2005, the following deferral election rules shall apply:



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2.2Amount of Deferral.Each participant may elect in his or her deferral agreement to defer 25 percent,
50 percent, 75 percent or 100 percent of the total cash compensation paid to the participant as an outside director of Genzyme.

2.3Deferral Account.For bookkeeping purposes only, the Secretary will establish and maintain an account (the
"deferral account") for each participant that documents the compensation deferred by the participant, earnings credited to the account and payments from the account. The deferral account will consist
of a subaccount for amounts earning interest, which will be denominated on a dollar basis (the "cash account"), and a subaccount for amounts invested in hypothetical shares of Genzyme Common Stock,
$0.01 par value ("Genzyme Stock") which will be denominated on a share basis (the "stock account"). Each participant will indicate in his or her deferral agreement the percentage of future deferrals
to be invested in the cash account and the stock account. Amounts may not be transferred between the cash account and the stock account.

2.4Cash Account.As of the first day of each calendar quarter, the Secretary will credit to the participant's
cash account an amount equal to the amount of compensation otherwise payable to the participant in the preceding calendar quarter that the participant has elected to defer and invest in the cash
account. As of the last day of each calendar quarter, the Secretary will credit interest on the balance in the cash account on that date at the rate paid on 90-day Treasury bills
hypothetically purchased on the first day of such calendar quarter. For a participant receiving installment payments, interest will be credited on the balance from time to time remaining in the cash
account until the account has been completely paid.

2.5Stock Account.As of the first day of each calendar quarter, the Secretary will credit to the participant's
stock account a number of shares of Genzyme Stock equal to the amount of compensation otherwise payable to the participant in the preceding calendar quarter that the participant has elected to defer
and invest in Genzyme Stock divided by the stock price for Genzyme Stock. The stock price shall mean the average of the closing price of Genzyme Stock for all trading days during the preceding
calendar quarter as reported by the NASDAQ National Market. As of the date of payment of any cash dividend on Genzyme Stock, the Secretary will credit to the stock account a number of shares of
Genzyme Stock equal to (i) the cash dividend per share times the number of shares credited to the stock account as of the dividend record date divided by (ii) the closing price for
Genzyme Stock on the date of payment of the dividend. As of the date of payment of any stock dividend on Genzyme Stock, the Secretary will credit to the stock account a number of shares equal to the
per-share stock dividend declared times the number of shares of Genzyme Stock credited to the stock account as of the dividend record date. In the event of any stock dividend,
recapitalization, reorganization, merger, consolidation, split-up, spin-off, exchange of shares or similar change affecting Genzyme Stock, appropriate

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adjustment
will be made in the number and/or kind of shares credited to the stock account. The stock account is maintained for bookkeeping purposes only, and shares credited to the stock account
represent a notional investment only. Prior to distribution to a participant under Section 3.3 or 3.4, a participant will have no rights as a stockholder with respect to amounts credited to the
stock account. Shares will include fractional shares computed to three decimal places.

2.6Shares Subject to the Plan.The aggregate number of shares of Common Stock which may be issued under the
plan is 105,962 shares of Genzyme Stock. In the event of any stock dividend, split-up, combination or reclassification of shares, recapitalization or similar capital change relating to the
common stock, the maximum aggregate number and kind of shares or securities of Genzyme that may be issued under the plan shall be appropriately adjusted by the Genzyme Board of Directors (whose
determination shall be conclusive).

ARTICLE III

PAYMENT OF DEFERRED COMPENSATION

3.1Commencement of Payment.



3.2Election of Form of Payment.



3.3Lump Sum Payments.



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3.4Installment Payments.



3.5Beneficiaries.



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3.6Payments on Death.



3.7Hardship Distributions from Accounts.



3.8Termination of Service.Termination of Service means the date on which a participant has a "separation from
service" (as defined at Treas. Reg. Section 1.409A-1(h)), including by reason of death, from Genzyme and from all other corporations and trades or businesses, if any, that would be
treated as a single "service recipient" with Genzyme under Treas. Reg. Section 1.409A-1(h)(3).

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ARTICLE IV

AMENDMENT AND TERMINATION

4.1Amendment.Genzyme may, without the consent of any participant, beneficiary or other person, amend the plan
at any time and from time to time. No amendment may reduce the amount credited to the deferral account of any participant. Any amendment that would cause a material modification of a benefit or right
existing as of October 4, 2004 and would result in a material benefit enhancement or addition affecting compensation earned and vested before January 1, 2005 will be ineffective and
rescinded before the earlier of the date the right is exercised (if the right is discretionary) or the last day of the calendar year during which the amendment is made.

4.2Plan Termination.Genzyme may terminate the plan at any time.



For
purposes of Section 4.2(b), the "Company" means the service recipient as defined under Treas. Reg. Section1.409A-1(g), generally meaning Genzyme and all
corporations within Genzyme's controlled group of corporations under Code Section 414(b) and all partnerships and affiliates of Genzyme within

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common
control as defined under Code Section 414(c). For purposes of (ii) above, however, the identity of the Company will be determined immediately after the change in control event.



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