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EXHIBIT 21

SUBSIDIARIES OF THE REGISTRANT

Name	Direct Parent(s)	Ownership		Jurisdiction of Incorporation
BioMarin/Genzyme LLC	Genzyme Corporation	50	%	Delaware
Genzyme Europe B.V.	Imtix SangStat (Switzerland) GmbH	100	%	The Netherlands
Genzyme Flanders N.V.	Genzyme International Holdings	100	%	Belgium
Genzyme GmbH	Genzyme Europe B.V.	100	%	Germany
Genzyme International Holdings Limited	SangStat Luxembourg S.à.r.l.	100	%	Ireland
Genzyme Ireland Limited	Genzyme International Holdings Limited	100	%	Republic of Ireland
Genzyme Limited	Genzyme Corporation	100	%	United Kingdom
Genzyme Securities Corporation	Genzyme Corporation	100	%	Masssachusetts
Genzyme Pharmaceuticals AG	SangStat Luxembourg S.à.r.l.	100	%	Switzerland
Genzyme Polyclonals S.A.S.	SangStat Medical, LLC SangStat Atlantique S.A.S.	1 99	% %	France
Imtix SangStat (Switzerland) GmbH	SangStat Luxembourg S.à.r.l.	100	%	Switzerland
SangStat Atlantique S.A.S.	SangStat Medical, LLC	100	%	France
SangStat Luxembourg S.à.r.l.	Genzyme Luxembourg S.à.r.l.	100	%	Luxembourg

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EXHIBIT 21