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EXHIBIT 21

SUBSIDIARIES OF THE REGISTRANT

Name	Direct Parent(s)	Ownership			Jurisdiction of Incorporation
Genzyme Europe B.V.	Imtix SangStat (Switzerland) GmbH		100	%	The Netherlands
Genzyme Flanders BVBA	Genzyme International Holdings Limited		99.9	%	Belgium
	Genzyme Global S.à.r.l.		0.1	%
Genzyme International Holdings Limited	Genzyme Global S.à.r.l.		100	%	Republic of Ireland
Genzyme Ireland Limited	Genzyme International Holdings Limited		100	%	Republic of Ireland
Genzyme Limited	Genzyme Global S.à.r.l		100	%	England
Genzyme Securities Corporation	Genzyme Therapeutic Products Limited Partnership		100	%	Massachusetts, United States
Genzyme Polyclonals S.A.S.	SangStat Medical, LLC		0.1	%	France
	SangStat Atlantique S.A.S.		99.9	%
Genzyme Therapeutic Products Limited Partnership	Genzyme Therapeutic Products Corporation		1	%	Massachusetts, United States
	Genzyme Corporation		99	%
Genzyme Therapeutic Products Corporation	Genzyme Corporation		100	%	Massachusetts, United States
Imtix SangStat (Switzerland) GmbH	Genzyme Global S.à.r.l.		100	%	Switzerland
SangStat Atlantique S.A.S.	SangStat Medical, LLC		100	%	France
Genzyme Global S.à.r.l.	Genzyme Luxembourg S.à.r.l.		100	%	Luxembourg
Genzyme Luxembourg S.à.r.l.	Genzyme Corporation		100	%	Luxembourg

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EXHIBIT 21

SUBSIDIARIES OF THE REGISTRANT