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                                                                      Exhibit 99

                IMPORTANT FACTORS REGARDING FORWARD-LOOKING STATEMENTS

                                      March 1998

     From time to time, Genzyme Transgenics Corporation ("GTC" or the 
"Company"), through its management, may make forward-looking public 
statements, such as statements concerning then expected future revenues or 
earnings or concerning projected plans, performance, product development and 
commercialization as well as other estimates relating to future operations. 
Forward-looking statements may be in reports filed under the Securities 
Exchange Act of 1934, as amended (the "Exchange Act"), in press releases or 
in oral statements made with the approval of an authorized executive officer. 
 The words or phrases "will likely result," "are expected to," "will 
continue," "is anticipated," "estimate," "project," or similar expressions 
are intended to identify "forward-looking statements" within the meaning of 
Section 21E of the Exchange Act and Section 27A of the Securities Act of 
1933, as amended, as enacted by the Private Securities Litigation Reform Act 
of 1995.

     The Company wishes to caution readers not to place undue reliance on 
these forward-looking statements which speak only as of the date on which 
they are made.  In addition, the Company wishes to advise readers that the 
factors listed below, as well as other factors not currently identified by 
management, could affect the Company's financial or other performance and 
could cause the Company's actual results for future periods to differ 
materially from any opinions on statements expressed with respect to future 
periods or events in any current statement.

     The Company will not undertake and specifically declines any obligation 
to publicly release any revisions which may be made to any forward-looking 
statements to reflect events or circumstances after the date of such 
statements or to reflect the occurrence of anticipated or unanticipated 
events which may cause management to re-evaluate such forward-looking 
statements.

     In connection with the "safe harbor" provisions of the Private 
Securities Litigation Reform Act of 1995, the Company is hereby filing 
cautionary statements identifying important factors that could cause the 
Company's actual results to differ materially form those projected in 
forward-looking statements of the Company made by or on behalf of the Company.

     History of Operating Losses; Need for Additional Funds.  GTC has had 
operating losses since its inception and expects such losses to continue for 
the next several years.  For the period from its inception in 1993 to 
December 28, 1997, the Company incurred cumulative losses of approximately 
$27.3 million. GTC's losses have resulted principally from costs incurred in 
connection with research activities and from expenses in excess of revenues 
from the Company's contract research organization ("CRO") services.  GTC's 
sources of revenues to date have consisted primarily of research and 
development contracts and CRO services.  Such revenues to date have not been 
sufficient to generate profits. The 

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Company expects to continue to incur significant operating losses until such 
time as product sales and CRO service revenues are sufficient to fund its 
operations.  No assurance can be given that the Company will become 
profitable.

     The Company currently believes that existing cash resources and 
available financing will be sufficient to meet its operating cash flow needs 
and capital requirements at least for the next year.  The development of 
transgenic products by the Company will require the commitment of substantial 
resources to conduct costly and time-consuming research, preclinical testing 
and clinical trials necessary to bring such products to market.  If GTC's 
businesses do not achieve profitable operations at or prior to the time such 
existing resources are exhausted, the Company will need to obtain additional 
financing, through public or private financings, including debt or equity 
financings, or through collaborative or other arrangements with corporate 
partners, as appropriate. Adequate funds for the Company's operations from 
such sources may not be available when needed or on terms acceptable to the 
Company.  If additional financing cannot be obtained when needed or on 
acceptable terms, GTC could be forced to delay, scale back or eliminate 
certain of its research and development programs or to license to other 
parties rights to commercialize products or technologies that the Company 
would otherwise seek to develop internally as well as delaying or forgoing 
timely expansion, improvement or investment in the Company's contract 
research services.

     The foregoing forward-looking statements regarding the Company's 
expectations of the need for additional funds are subject to risks and 
uncertainties.  The Company's cash requirements may vary materially from 
those now planned, depending upon the results of existing businesses, the 
terms of future collaborations, results of research and development, 
competitive and technological advances, regulatory requirements and other 
factors.

     Early Stage of Transgenic Technology.  Development of products based on 
transgenic technology is subject to a number of significant technological 
risks and the time period required for any such development is both lengthy 
and uncertain.  Neither GTC nor, to GTC's knowledge, any other entity has 
completed human clinical trials of any protein produced in the milk of 
transgenic animals, and there can be no assurance that GTC will be able to do 
so successfully. There can be no assurance that any transgenically produced 
protein will be safe or effective.  All of the proteins that GTC is 
developing will require significant additional research, development and 
testing and will require the expenditure of substantial additional capital 
prior to their commercialization. In addition, there can be no assurance that 
research and discoveries by others will not render GTC's technology obsolete 
or noncompetitive.

     No Assurance of Commercial Success of Transgenic Products.  The 
successful commercialization of any transgenic protein product by the Company 
will depend on many factors, including the successful completion of clinical 
testing, the response of medical professionals to the data from clinical 
trials, the Company's ability to create or access a sales force able to 
market such transgenic products, the Company's ability to supply a sufficient 
amount of product to meet market demand, the degree to which third-party 
reimbursement for use of such product is available and the number and 
relative efficacy of competitive products that may subsequently enter the 
market, as well as, with respect to transgenic products designed to replace 
or supplement products currently being marketed, the relative 
cost-effectiveness of the transgenic products.  There can be no assurance 
that the Company or its collaborative partners 

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will be successful in efforts to develop and implement a commercialization 
strategy for any such products.

     GTC does not currently have a sales force to market any transgenic 
products it may develop.  The Company anticipates that, for products it 
develops independently, it will enter into marketing arrangements with larger 
pharmaceutical or biotechnology companies which have established sales forces 
that are able to market such products.  There can be no assurance that any 
marketing or distribution arrangements will be available on acceptable terms 
or that, in the alternative, GTC will be able to establish its own sales 
force successfully.  Unforeseen delays in this process may have an adverse 
effect on the commercialization of any of the Company's products.

     Third-party payors are increasingly attempting to contain health care 
costs by limiting both coverage and the level of reimbursement for new 
therapeutic products.  The successful commercialization of any products 
developed by the Company may depend on obtaining coverage and reimbursement 
for the use of these products from third-party payors.

     In addition, the successful commercialization of the Company's products 
will require that medical professionals become convinced of the efficacy of 
the products in treating a particular condition and incorporate such products 
as standard practice in relevant therapeutic protocols.  There can be no 
assurance that any transgenic product developed by GTC will be accepted by 
the medical profession.

     Government Regulation.  Transgenic products will require approval by the 
U.S. Food and Drug Administration ("FDA") prior to marketing in the United 
States.  In addition, the manufacturing and marketing of such products, and 
certain areas of research related to them, are subject to regulations by 
other U.S. governmental authorities including the United States Department of 
Agriculture (the "USDA") and the Environmental Protection Agency (the "EPA"). 
Comparable authorities are involved in other countries.

     In cases where the Company expects to obtain revenue from the sale of 
transgenic products, whether through direct sales, marketing relationships 
with others or royalty arrangements, the Company will incur the risk of such 
product failing to satisfy applicable regulatory requirements prior to 
marketing.  The approval process involves two parts, governing first the 
approval of an individual pharmaceutical product as safe and effective and 
second the approval of the manufacturing process as complying with applicable 
FDA current good manufacturing practices regulations ("GMPs").  In 1995, the 
FDA and comparable European regulatory authorities issued guidelines 
regarding the production of therapeutic proteins in transgenic animals.  
While the FDA's guidelines, known as Points to Consider guidelines ("Points 
to Consider"), cover issues specific to transgenic production, the basic 
regulatory framework for FDA approval will also apply to transgenic 
therapeutic products submitted for approval.  To GTC's knowledge, no protein 
produced in the milk of a transgenic animal has been submitted for regulatory 
approval in the United States or elsewhere.

     The FDA and comparable agencies in foreign countries impose substantial 
requirements upon the introduction of therapeutic pharmaceutical products 
through lengthy and detailed laboratory and clinical testing procedures, 
sampling activities and other costly and time-consuming 

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procedures.  Satisfaction of these requirements typically takes several years 
or more and can vary substantially based upon the type, complexity and 
novelty of the product.  With respect to therapeutic products, the standard 
FDA approval process includes preclinical laboratory and animal testing, 
submission of an IND to the FDA, appropriate human clinical trials to 
establish safety and effectiveness and submission of either a Biologics 
License Application or a New Drug Application ("NDA") prior to market 
introduction.  With respect to obtaining approval for the production 
facilities to be used in producing a therapeutic product, the Company expects 
to be subject to both the requirements for establishment license applications 
and the Points to Consider issued with respect to transgenic recombinant 
products.

     The effect of government regulation may be to delay marketing of the 
Company's products for a considerable or indefinite period of time, impose 
costly procedural requirements upon the Company's activities and may furnish 
a competitive advantage to larger companies or companies more experienced in 
regulatory affairs.  There can be no assurance that the FDA or other 
regulatory approvals for any products developed by the Company will be 
granted on a timely basis or at all.  Any delay in obtaining or any failure 
to obtain such approvals could adversely affect the Company's ability to 
generate revenue.  Even if initial regulatory approvals for the Company's 
product candidates are obtained, the Company, its products and its transgenic 
manufacturing processes would be subject to continual review and periodic 
inspection.  There can be no assurance that the FDA will permit the marketing 
of any transgenic product for any particular indication, if at all.

     The Company's operations are also subject to federal, state and local 
laws, rules, regulations and policies governing the use, generation, 
manufacture, storage, air emission, effluent discharge, handling and disposal 
of certain materials and waste, including but not limited to animal waste and 
waste water.

     Dependence of Testing Services on Current Government Regulatory 
Requirements.  The market for GTC's preclinical testing services is dependent 
upon the maintenance of strict standards for the conduct of laboratory and 
clinical tests and related procedures which are promulgated by governmental 
entities responsible for public health and welfare, including the FDA, and by 
regulatory authorities in foreign countries.  The process of obtaining these 
approvals varies according to the nature and use of the product and routinely 
involves lengthy and detailed laboratory and clinical testing and other 
costly and time-consuming procedures.  The Company offers the customers of 
its preclinical testing and development services the necessary expertise to 
comply with these complex regulations.  If the regulatory structure were to 
change in a way which reduced the need for such services, the Company could 
be materially adversely affected.

     Dependence on Genzyme.  GTC has entered into a number of contractual 
agreements with Genzyme, including a research and development agreement 
pursuant to which Genzyme provides purification services to GTC for 
transgenically produced proteins (the "Genzyme R&D Agreement"), a lease of 
GTC's facility in Framingham, Massachusetts, and an agreement to provide 
funding for the development of AT-III (the "Genzyme Collaboration Agreement").

     Under the Genzyme R&D Agreement, Genzyme is obligated to use 
commercially reasonable efforts to perform purification services for GTC.  
GTC does not currently have personnel 

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capable of undertaking such purification services.  Until such time, if ever, 
as GTC develops its own capabilities in this regard, there can be no 
assurance that Genzyme will be able to provide such services when and as 
required by GTC or that GTC would be able to obtain comparable services 
elsewhere.

     Under the Genzyme Collaboration Agreement, Genzyme has agreed to provide 
funding for transgenic AT-III development in exchange for co-marketing rights 
to AT-III in all territories other than Asia.  The term of the agreement is 
perpetual, except that either party may terminate the agreement for certain 
material breaches, failure to make payments, and either upon the grant, or 
certain absences of a grant, by the FDA of a license to market an AT-III 
product.  There can be no assurance, should the agreement terminate before 
completion of the development of an AT-III product, that Genzyme and GTC 
could reach an agreement to extend Genzyme's development funding, that the 
Company would be able to fund such program on its own or that the Company 
would be able to obtain such funding from a third party on acceptable terms, 
if at all.

     Potential Conflicts of Interest with Genzyme.  Genzyme is the largest 
single stockholder of GTC.  Assuming exercise of a currently exercisable 
warrant for 145,000 shares of Common Stock, Genzyme beneficially owns 
approximately 44% of the outstanding Common Stock of GTC.

     Genzyme's ownership interest gives it significant influence over any 
election of directors and any other action requiring approval by the holders 
of a majority of the Common Stock.  Three members of GTC's Board of Directors 
also serve as directors and/or executive officers of Genzyme.  The interests 
of Genzyme on the one hand and GTC on the other hand may, from time to time, 
differ.

     Dependence on Collaborators.  The success of GTC's transgenic protein 
production business will depend, in large part, on GTC's ability to enter 
into arrangements with biotechnology and pharmaceutical companies for the 
transgenic production of proteins to which such companies have proprietary 
rights or to fund the development of transgenic proteins which are in the 
public domain or the subject of expiring patents.  To date, the scope of 
these agreements has generally been limited to demonstrating the feasibility 
of transgenic production of targeted proteins in particular animal species.  
There can be no assurance that these feasibility studies will be successful 
or lead to agreements for the commercial production of any proteins.  
Depending upon the terms of any future collaborations, the Company's role in 
such collaborations may be limited to the production aspects of the proteins 
under development.  As a result, GTC may also be dependent on collaborators 
for other aspects of the development, preclinical and clinical testing, 
regulatory approval and commercialization of any transgenic product.

     Uncertainty Regarding Patents and Proprietary Technology.  GTC has 
relied upon trade secrets, proprietary know-how and continuing technological 
innovation to develop and maintain its competitive position and to protect 
its proprietary technology.  In part, these legal rights are protected by 
contracts with employees, consultants and business partners.  There can be no 
assurance that trade secrets possessed by GTC will be maintained, that 
secrecy obligations will be honored or that others will not independently 
develop similar or superior technology.  There is no assurance that patent 
applications filed by GTC will result in patents being issued or that 

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any patents issued to or licensed by GTC will be held valid.  The Company may 
also be subject to claims that result in the revocation of patent rights 
previously licensed to GTC as a result of which the Company may be required 
to obtain licenses from others to continue to develop, test or commercialize 
its products.  There can be no assurance that GTC will be able to obtain such 
licenses on acceptable terms, if at all.  In addition, there may be pending 
or issued patents held by parties not affiliated with GTC that relate to the 
technology utilized by GTC.  As a result, GTC may need to acquire licenses 
to, or contest the validity of, such patents or any other similar patents 
which may be issued.  GTC could incur substantial costs in defending itself 
against challenges to patent or infringement claims made by third parties or 
in enforcing any patent rights of its own.  The loss or exposure of trade 
secrets possessed by GTC could also adversely affect its business.

     Risk of Service or Product Liability.  GTC's business exposes it to 
potential product and professional liability risks which are inherent in the 
testing, production, marketing and sale of human therapeutic products.  While 
GTC has obtained product and professional liability insurance under an 
insurance policy arrangement with Genzyme and Genzyme's affiliates, there can 
be no assurance that such insurance will be sufficient to cover any claim.  
Uninsured product or service liability could have a material adverse effect 
on the financial results of GTC.  In addition, there can be no assurance that 
any insurance will provide GTC with adequate protection against potential 
liabilities.  Potential liability also may arise from the handling by GTC of 
clinical samples containing human blood and tissues, which may contain human 
pathogens; liability may also arise from handling animal blood and tissue 
which may contain zoonotic pathogens.  Although such products are used only 
in the laboratory, inadvertent human contact may occur.

     Retention of Key Personnel.  Although GTC believes that the size and 
qualifications of its current staff are adequate for its current business, 
the Company must continue to attract and retain qualified scientific, 
technical, marketing and management personnel as its business expands.  There 
is intense competition for qualified personnel in the areas of the Company's 
activities, and there can be no assurance that GTC will be able to continue 
to attract and retain the qualified personnel necessary for the development 
of its business. Loss of the services of, or failure to recruit, key 
scientific and technical personnel could have a material adverse effect on 
GTC's business.

     Public Concerns.  Certain of GTC's activities involve animal testing and 
genetic engineering in animals.  Such activities have been the subject of 
controversy and adverse publicity.  Animal rights groups and various other 
organizations and individuals have attempted to stop animal testing and 
genetic engineering activities by pressing for legislation and regulation in 
these areas.  To the extent the activities of such groups are successful, 
GTC's business may be adversely affected.

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