Exhibit 3.1

The Commonwealth of Massachusetts
William Francis GalvinSecretary of the Commonwealth
One Ashburton Place, Boston, Massachusetts 02108-1512

Restated Articles of Organization

(General Laws Chapter 156D, Section 10.07; 950 CMR 113.35)

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|(1) Exact name of corporation:                Genzyme Corporation 061047163
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|(2) Registered office address:                500 Kendall Street, Cambridge, MA 02142
|                                                                                      |  | (number, street, city or town, state, zip code)

|(3) Date adopted:                May 25, 2006
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OR

ARTICLE IThe exact name of the corporation is:



ARTICLE II

Unless
the articles of organization otherwise provide, all corporations formed pursuant to G.L. Chapter 156D have the purpose of engaging in any lawful business. Please specify if you want a more
limited purpose:**

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ARTICLE III

State
the total number of shares and par value, *if any, of each class of stock that the corporation is authorized to issue. All corporations must authorize stock. If only one class or series is
authorized, it is not necessary to specify any particular designation.

|Without Par Value |  | With Par Value
|----------------- |  | --------------
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ARTICLE IV

Prior
to the issuance of shares of any class or series, the articles of organization must set forth the preferences, limitations and relative rights of that class or series. The articles may also
limit the type or specify the minimum amount of consideration for which shares of any class or series may be issued. Please set forth the preferences, limitations and relative rights of each class or
series and, if desired, the required type and minimum amount of consideration to be received.

See Attachment IV for Description of Capital Stock

ARTICLE V

The restrictions, if any, imposed by the articles or organization upon the transfer of shares of any class or series of stock are:

None

ARTICLE VI

Other lawful provisions, and if there are no such provisions, this article may be left blank.

See Attachment VI for Other Lawful Provisions

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Note: The preceding six (6) articles are considered to be permanent and may be changed only by filing appropriate articles of amendment.

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ARTICLE VII

The
effective date of organization of the corporation is the date and time the articles were received for filing if the articles are not rejected within the time prescribed by law. If a later
effective date is desired, specify such date, which may not be later than the 90th day after the articles are received for filing:

It
is hereby certified that these restated articles of organization consolidate all amendments into a single document. If a new amendment authorizes an exchange, or effects a reclassification or
cancellation, of issued shares, provisions for implementing that action are set forth in these restated articles unless contained in the text of the amendment.

Specify
the number(s) of the article(s) being amended: Articles II, IV, VI

|Signed by: | /s/ Peter Wirth(signature of authorized individual)
|---------- | ---------------------------------------------------

o Chairman of the board of directors,

o President,

ý Other officer,

o Court-appointed fiduciary,

on this 25th day of May, 2006.

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Attachment IV to Restated Articles of Organization

DESCRIPTION OF CAPITAL STOCK

A. AUTHORIZED CAPITAL STOCK

The
total number of shares of all classes of capital stock which the Corporation shall be authorized to issue is seven hundred million (700,000,000) shares, consisting of six hundred
ninety million (690,000,000) shares of Common Stock, $.01 par value per share (the "Common Stock") and ten million (10,000,000) shares of Preferred Stock, $.01 par value per share (the "Preferred
Stock"). The board of directors, at any time or from time to time may reclassify any unissued shares of any class or series of capital stock into one or more existing or new classes or series.

B. DESCRIPTION OF COMMON STOCK

The holders of outstanding shares of Common Stock shall have the exclusive right to vote for the election of directors and on all other matters requiring action
by the shareholders or submitted to the shareholders for action, except as may be provided herein, as may be associated with any series of Preferred Stock, or as may be otherwise required by law. Each
share of Common Stock shall entitle the holder thereof to one vote.

Subject
to the terms of any outstanding series of Preferred Stock, the holders of outstanding shares of Common Stock shall be entitled to receive, to the extent permitted by law, such
dividends as may from time to time be declared by the Board of Directors.

Upon
any voluntary or involuntary liquidation, dissolution or winding up of the Corporation, the holders of the Common Stock shall be entitled to receive the net assets of the
Corporation, after the Corporation shall have satisfied or made provision for its debts and obligations and for payment to the holders of shares of any series of Preferred Stock having preferential
rights to receive distributions of the net assets of the Corporation.

C. DESCRIPTION OF THE PREFERRED STOCK

1.Undesignated Preferred Stock.Shares of Preferred Stock may be issued from time to time in one or more series. The Board
of Directors may determine, in whole or in part, the number, preferences, limitations or relative rights of any such series before the issuance of any shares of that series.

2.Terms of The Series A Junior Participating Preferred Stock.



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Attachment VI to Restated Articles of Organization

OTHER LAWFUL PROVISIONS

A. BOARD OF DIRECTORS

1.Election.The directors currently are divided into three classes, as nearly equal in number as the total number of
directors constituting the entire Board permits. Directors shall serve until their respective successors shall be elected and qualified, subject to prior death, resignation, retirement or removal. At
the 2006 annual meeting of shareholders, the successors of the directors whose terms expire at that meeting shall be elected for terms expiring at the 2009 annual meeting of shareholders; at the 2007
annual meeting of shareholders, the successors of the directors whose terms expire at that meeting shall be elected for terms expiring at the 2008 annual meeting of shareholders; and at the 2008
annual meeting of shareholders, the successors of the directors whose terms expire at that meeting shall be elected for terms expiring at the 2009 annual meeting of shareholders. Thereafter all
directors shall be elected for terms expiring at the next annual meeting of shareholders and until their successors shall be elected and qualified, subject to prior death, resignation, retirement or
removal. In no event will a decrease in the number of directors shorten the term of any incumbent director. Notwithstanding the foregoing, and except as otherwise required by law, whenever the holders
of any one or more series of Preferred Stock shall have the right, voting separately as a class, to elect one or more directors of the Corporation, the election, terms of office and other features of
such directorships shall be governed by the terms of the vote establishing such series.

2.Vacancies.Except as otherwise determined by the Board of Directors in establishing a series of Preferred Stock as to
directors elected by holders of such series, any vacancies in the Board of Directors, including a vacancy resulting from the enlargement of the Board of Directors, shall be filled by the directors
then in office, though less than a quorum. Each director chosen to fill a vacancy not resulting from an enlargement of the Board of Directors shall be elected to complete the term of office of the
director who is being succeeded and until a successor shall be elected and qualified, subject to prior death, resignation, retirement or removal. In the case of a vacancy resulting from the
enlargement of the Board of Directors, the director shall be elected for a term expiring at the next annual meeting of shareholders and until a successor shall be elected and qualified, subject to
prior death, resignation, retirement or removal.

3.Removal.Except as otherwise determined by the Board of Directors in establishing a series of Preferred Stock as to
directors elected by holders of such series, at any special meeting of the shareholders called at least in part for the purpose, any director or directors may, by the affirmative vote of the holders
of at least a majority of the stock entitled to vote for the election of directors, be removed from office for cause. The provisions of this subsection shall be the exclusive method for the removal of
directors.

B. SHAREHOLDER VOTE REQUIRED FOR CERTAIN ACTIONS

The Corporation, by vote of a majority in interest of the stock outstanding and entitled to vote thereon may approve (i) any amendment to these Articles of
Organization, (ii) the sale, lease, exchange, or other disposal of all or substantially all of the Corporation's property, (iii) a merger or consolidation of the Corporation with or into
any other entity; or (iv) a share exchange with any other entity, in each case, so long as such amendment, sale, lease, exchange, disposal, merger, consolidation, or share exchange shall have
been approved by the Board of Directors. This provision is not intended to, and shall not, create a requirement to obtain shareholder approval for transactions that do not require shareholder approval
under applicable Massachusetts corporation law.

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C. ADDITIONAL PROVISIONS

1.     No
contract or other transaction of this Corporation with any other person or entity shall be affected or invalidated by the fact that (i) this Corporation is a
shareholder or partner in such other corporation, association, or partnership, or (ii) any one or more of the officers or directors of this Corporation is an officer, director or partner of
such other corporation, association or partnership, or (iii) any officer or director of this Corporation, individually or jointly with others, is a party to or is interested in such contract or
transaction. Any director of this Corporation may be counted in determining the existence of a quorum at any meeting of the board of directors for the purpose of authorizing or ratifying any such
contract or transaction, and may vote thereon, with like force and effect as if he were not so interested or were not an officer, director, or partner of such other corporation, association, or
partnership.

2.     The
bylaws may provide that the directors may make, amend, or repeal the bylaws in whole or in part, except with respect to any provision thereof which by law, these
Articles of Organization, or the bylaws requires action by the shareholders.

3.     A
director shall not be liable to the Corporation or its shareholders for monetary damages for any breach of fiduciary duty as a director, except to the extent that the
elimination or limitation of liability is not permitted under Massachusetts corporation law, as in effect when such liability is determined. No amendment or repeal of this provision shall deprive a
director of the benefits hereof with respect to any act or omission occurring prior to such amendment or repeal.

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COMMONWEALTH OF MASSACHUSETTS

William
Francis Galvin
Secretary of the Commonwealth
One Ashburton Place, Boston, Massachusetts 02108-1512

Restated Articles of Organization(General LawsChapter 156D, Section 10.07; 950CMR 113.35)

I
hereby certify that upon examination of these restated articles of organization, duly submitted to me, it appears that the provisions of the General Laws relative to the organization of corporations
have been complied with, and I hereby approve said articles; and the filing fee in the amount of $500 having been paid, said articles are deemed to have been filed with me this 25th day of May, 2006,
at 2:48 p.m.

Effective
date:____________________________________________________________

(must be within 90 days of date submitted)

/s/ WILLIAM FRANCIS GALVIN
WILLIAM FRANCIS GALVIN Secretary of the Commonwealth

Filing
fee: Minimum filing fee $200, plus $100 per article amended, stock increases $100 per 100,000 shares, plus $100 for each additional 100,000 shares or any fraction thereof.

TO
BE FILLED IN BY CORPORATION
Contact Information:

Genzyme
Corporation
500 Kendall Street, Cambridge, MA 02142
Attn: Peter Wirth, Secretary
Telephone: 617-252-7500
Email:

Upon
filing, a copy of this filing will be available at www.sec.state.ma.us/com. If the document is rejected, a copy of the rejection sheet and rejected document will be available in the
rejected queue.

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