Exhibit 99.1

CONTACTS:

For BioMarin                                         For Genzyme
Joshua Grass (Investors)                             Bo Piela (Media)
(415) 884-6777                                       (617) 252-7785

Fredda Malkoff (media)                               Sally Curley (investors)
Feinstein Kean Healthcare                            (617) 591-7140
(617) 577-8110

For Immediate Release
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      BioMarin and Genzyme Complete `Rolling' BLA Filing for AldurazymeTM

Novato,  CA and  Cambridge,  MA,  July 29, 2002 - BioMarin  Pharmaceutical  Inc.
(Nasdaq and Swiss SWX New Market: BMRN) and Genzyme General (Nasdaq: GENZ) today
announced  that the companies  submitted  the final  portion of their  `rolling'
Biologics License Application (BLA) for Aldurazyme(TM)  (laronidase) to the U.S.
Food and Drug  Administration  (FDA).  The  final  portion  of the BLA  includes
clinical  data  from  the  six-month,   placebo-controlled   Phase  3  trial  of
Aldurazyme,  six months of data from the  ongoing  open-label  Phase 3 extension
study,  and three  years of data from the  Phase 1 trial  and  extension  study.
Aldurazyme is an investigational  enzyme  replacement  therapy for patients with
mucopolysaccharidosis I (MPS I), a life-threatening genetic disease for which no
specific drug treatments currently exist.

As part of the BLA  submission,  BioMarin  and Genzyme have  formally  requested
Priority Review,  which is an FDA procedure generally reserved for products that
address an unmet medical need. The companies  expect a decision  regarding FDA's
acceptance of the  Aldurazyme  BLA and its Priority  Review status by the end of
September  2002.  If the FDA accepts  the BLA and grants  Priority  Review,  the
companies anticipate a response from the FDA regarding the application to market
Aldurazyme  in the  United  States six months  from the  submission  date of the
completed application.

On March 1, 2002,  BioMarin  and Genzyme  submitted  a  Marketing  Authorization
Application  (MAA)  to the  European  Agency  for the  Evaluation  of  Medicinal
Products  (EMEA) for approval to market  Aldurazyme in the European  Union.  The
Agency has accepted the MAA and is currently reviewing the application. BioMarin
and Genzyme expect a response from the EMEA in the first half of 2003.

About MPS I
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MPS I (historically known as Hurler,  Hurler-Scheie,  and Scheie syndromes) is a
life-threatening   genetic   disease  caused  by  a  deficiency  of  the  enzyme
alpha-L-iduronidase.  This  deficiency  leads  to the  accumulation  of  complex
carbohydrates  (GAGs) in the  lysosomes  of cells,  leading  to the  progressive
dysfunction  of  cellular,  tissue and organ  systems.  Resulting  symptoms  can
include impaired cardiac and pulmonary function,  delayed physical  development,
skeletal and joint deformities,  reduced endurance,  and in some cases,  delayed
mental function.  A majority of patients die before adulthood from complications
of the disease.

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BioMarin and Genzyme formed a joint venture in 1998 to develop and commercialize
Aldurazyme  worldwide.  Under the terms of the joint  venture,  if approved  for
commercial  sale,  BioMarin will  manufacture  Aldurazyme  and Genzyme will have
responsibility  for the  commercialization  of the product.  The companies  have
obtained Orphan Drug  designation and Fast Track status for Aldurazyme for MPS I
from the FDA and orphan medicinal product designation from the EMEA.

Genzyme  General  develops  and  markets  therapeutic  products  and  diagnostic
products and  services.  Genzyme  General has five  therapeutic  products on the
market and a strong pipeline of therapeutic  products in development  focused on
the treatment of genetic diseases and other chronic debilitating  disorders with
well-defined patient populations. Genzyme General is a division of Genzyme Corp.

BioMarin Pharmaceutical  specializes in the development and commercialization of
therapeutic  enzyme  products to treat  serious,  life-threatening  diseases and
conditions.

This  press  release  contains  forward-looking  statements,  including  without
limitation  statements  about:  decisions  by the FDA and  the  expected  timing
thereof;   the  potential  approval  of  Aldurazyme  for  commercial  sale;  and
commercialization plans. These statements are subject to risks and uncertainties
that could cause actual  results to differ  materially  from those  projected in
these forward-looking  statements.  These risks and uncertainties include, among
others:  the  content  and  timing  of  decisions  made by the FDA and the  EMEA
regarding  regulatory  submissions  for  Aldurazyme;  the ability to manufacture
sufficient quantities of product for  commercialization  activities and to do so
in a timely manner;  the continued  funding of the joint venture between Genzyme
and BioMarin;  decisions made by physicians and third party payers regarding the
use of and  reimbursement  for  Aldurazyme;  our ability to obtain and  maintain
adequate patent and other  proprietary  rights  protection for  Aldurazyme;  the
scope,  validity and enforceability of patents and other proprietary rights held
by third  parties  related to therapies  for MPS I and the actual impact of such
patents  and other  rights  on our  ability  to  commercialize  Aldurazyme;  the
competitive environment for therapies for MPS I; and the risks and uncertainties
described  in reports  filed by Genzyme and  BioMarin  with the  Securities  and
Exchange  Commission  under the  Securities  Exchange  Act of 1934,  as amended,
including  without  limitation the factors  contained under the caption "Factors
Affecting  Future  Operating  Results" in Exhibit 99.2 to Genzyme  Corporation's
2001 Annual  Report on Form 10-K.  Genzyme  General  Division  common stock is a
series of common  stock of Genzyme  Corporation.  Therefore,  holders of Genzyme
General Division common stock are subject to all of the risks and  uncertainties
described in the those reports.  Genyzme and BioMarin  caution  investors not to
place undue reliance on the forward-looking  statements  contained in this press
release.  These statements speak only as of the date of this press release,  and
Genzyme and BioMarin undertake no obligation to update or revise the statements.

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Genzyme(R) is a registered trademark of Genzyme  Corporation.  AldurazymeTM is a
trademark of BioMarin/Genzyme LLC. All rights reserved.

                                   # # #

Genzyme's  press  releases  and  other  company  information  are  available  at
www.genzyme.com   and  by  calling  Genzyme's   investor   information  line  at
1-800-905-4369  within the United  States or  1-703-797-1866  outside the United
States.

BioMarin's press releases and other company  information are available online at
http://www.biomarinpharm.com.

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