EXHIBIT 99.1

Tuesday December 14, 8:16 am Eastern Time

Company Press Release

SOURCE: American Cyanamid Company

AMERICAN CYANAMID AND HYSEQ SIGN BROAD SCALE GENE PRODUCT AGREEMENT

PARSIPPANY, N.J., and SUNNYVALE, Calif., Dec. 14 /PRNewswire/ -- American
Cyanamid Company, a subsidiary of American Home Products Corporation (NYSE:
AHP) and Hyseq, Inc. (Nasdaq: HYSQ) announced today that they have entered
into a multi-year agreement to discover genes and develop gene products. The
collaboration involves Hyseq's high throughput genomics and bioinformatics
technologies. Hyseq will collaborate exclusively with American Cyanamid in
the agricultural field to use its proprietary technology and know-how to
develop products for use in crop protection, crop production and use as
nutraceuticals, human and animal foodstuffs, industrial products and chemical
intermediates, as well as plant-based production of pharmaceuticals.

"American Cyanamid has been using biotechnology in its research efforts for a
number of years, and was actually the first to market a herbicide tolerant
crop with the introduction of imidazolinone tolerant corn in 1992. We have
been developing an expanded biotechnology strategy for more than two years
now. Our initiatives will utilize both our proprietary technology and
research capabilities and external collaborations," said Dr. Mark Atwood,
president, Cyanamid Global Agricultural Products Research Division. "We
believe that this agreement with Hyseq allows us to take a quantum leap
forward in our genomics and bioinformation research and development. Hyseq's
proprietary technologies and know-how strengthen our genomics capability. We
are excited about how we will apply the results of these technologies to
improve the productivity and utilization of plants for a broad range of uses."

Under the terms the agreement, Hyseq will receive $60 million in revenues
over a 3.5 year period and future royalty payments for products originating
from the collaboration. Both companies retain the non-exclusive right to use
the results and technologies developed in the collaboration for applications
outside of agriculture and both will receive royalty payments for products
originating from the collaboration.

"Hyseq has used its proprietary technology to sift through over 12 million
samples for internal use, and over 6 million for our partners, to
functionally target manageable numbers of pharmaceutical product candidates,"
said Lewis S. Gruber, Hyseq's president and chief executive officer. "We are
pleased to combine Hyseq's expertise in genomics with American Cyanamid's
strong track record in aggressively developing and marketing technology-based
products and its global presence in agricultural production. We believe this
collaboration will provide the largest amount of information ever available
on genes with agricultural significance."

"Cyanamid is working to identify genes that can play an important role in
enhancing the value of crops. This agreement with Hyseq allows us to
accelerate our efforts," said Dr. Howard Minigh, president, Cyanamid Global
Agricultural Products. "Working with technology and marketing




partners, Cyanamid will continue to provide innovative solutions that will
add economic value to our customers and benefit consumers."

"With our focus on the development of biopharmaceuticals, such as our IL-1Hy1
potential anti-inflammatory and CD39-L4 potential anti-clotting drug
candidates, our collaboration with American Cyanamid in agriculture is an
ideal fit into Hyseq's business strategy," said Mark E. Gitter, Hyseq's chief
financial officer. "We are currently developing our product candidates that
came out of our screening process and look forward to repeating this success
with American Cyanamid."

American Cyanamid is a leading global developer and marketer of crop
protection products for agricultural, specialty and consumer markets.
Cyanamid produces and markets herbicides, insecticides and fungicides in the
major agricultural regions of the world. Cyanamid is a subsidiary of American
Home Products Corporation, one of the world's largest research-based
pharmaceutical and health care product companies. AHP is a leader in the
discovery, development, manufacturing and marketing of prescription drugs and
over-the-counter medications. It is also a global leader in vaccines,
biotechnology, agricultural products and animal health care.

Hyseq is a biopharmaceutical company with a growing pipeline of therapeutic
and diagnostic product candidates for meeting medical and healthcare needs.
Hyseq uses its proprietary technology with its partners for therapeutic and
diagnostic target discovery and pharmacogenomics and polymorphism analysis,
and in its DNA analysis tools such as the HyChip(TM) system. Information
about Hyseq is available at http://www.hyseq.com or by phoning 408-524-8100.
Hyseq's wholly owned subsidiary, GeneSolutions Inc., offers genomic resources
to pharmaceutical and biomedical researchers on the Internet at
http://www.genesolutions.com.

The statements in this press release that are not historical facts are
forward-looking statements for purposes of the safe harbor provided by the
Private Securities Litigation Act of 1995. Forward-looking statements may be
identified by words including "anticipate," "believe," "intends,"
"estimates," "expect" and similar expressions and that involve risks and
uncertainties including those detailed from time to time in the periodic
reports of AHP and Hyseq, including quarterly reports on Form 10 Q and the
respective company annual reports on Form 10-K, filed with the Securities and
Exchange Commission. Actual results may differ from the forward-looking
statements. Hyseq disclaims any intent or obligation to update its
forward-looking statements.