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Exhibit 12.1

GENZYME CORPORATION AND SUBSIDIARIES
Computation of Ratio of Earnings to Fixed Charges
(Amounts in thousands)

			Year Ended December 31,
			1999			2000			2001			2002		2003
Income (loss) before income taxes			$	117,928		$	(7,462	)	$	(118,343	)	$	104,211	$	5,055
Add: equity in loss of equity method investments				42,696			44,965			35,681			16,858		16,743
Deduct: minority interest				(3,674	)		(4,625	)		(2,259	)		—		(2,232	)
Income (loss) before income taxes, equity in loss of equity method investments and minority interest				156,950			32,878			(84,921	)		121,069		19,566
Add:
	Fixed charges:
		Portion of rents representative of the interest factor		7,533			9,233			11,233			11,833		15,233
		Amortization of debt issuance costs		1,333			1,148			2,638			2,964		3,311
		Interest expense		20,438			14,562			34,495			24,188		23,289
	Amortization of capitalized interest			3,021			3,287			3,829			4,178		5,132
	Minority interest in pre-tax loss of subsidiaries that have not included fixed charges			3,674			4,625			2,259			—		2,232
As adjusted income (loss)			$	192,949		$	65,733		$	(30,467	)	$	164,232	$	68,763
Fixed charges:
	Interest expense			20,438			14,562			34,495			24,188		23,289
	Capitalized interest			1,329			2,713			4,173			5,250		6,136
	Amortization of debt issuance costs			1,333			1,148			2,638			2,964		3,311
	Portion of rents representative of the interest factor			7,533			9,233			11,233			11,833		15,233
Total fixed charges			$	30,633		$	27,656		$	52,539		$	44,235	$	47,969
Ratio of earnings to fixed charges (1)				6.3x			2.4x			—			3.7x		1.4x

(1)

The ratio of earnings to fixed charges is not presented for the year ended December 31, 2001 because in such year fixed charges exceeded earnings (as set forth above) by $83.0 million primarily due to:

•

$95.6 million of charges for in-process research and development resulting from the acquisitions of Novazyme Pharmaceuticals, Inc. and Wyntek Diagnostics, Inc.; and

•

a loss of $25.0 million related to the sale of our Snowden-Pencer line of surgical instruments.

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GENZYME CORPORATION AND SUBSIDIARIES Computation of Ratio of Earnings to Fixed Charges (Amounts in thousands)