EXHIBIT 23
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (No. 033-21241, No. 333-55126, No. 333-111314, No. 333-125724 and No. 333-143467) of Genzyme Corporation of our report dated June 26, 2008 relating to the financial statements of the Genzyme Corporation 401(k) Plan, which appears in this Form 11-K.
/s/ PricewaterhouseCoopers LLP
Boston, Massachusetts
June 26, 2008
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