Duke University and Affymetrix Initiate Five-Year Translational Research Collaboration.

SANTA CLARA, Calif. & DURHAM, N.C. -- Affymetrix Inc. (Nasdaq:AFFX) announced today that it has entered into a five-year collaboration with Duke University to analyze genomic information across large patient samples. Under terms of the agreement, Duke researchers will use Affymetrix GeneChip(R) microarray technology to develop new applications for translational research projects. The initial projects will focus on cancer and cardiovascular disease.

Duke researchers will use Affymetrix' GeneChip HT (High-Throughput) System and arrays to perform large-scale clinical studies. The Affymetrix technology will enable them to more rapidly discover RNA and DNA patterns that can better classify, manage and treat complex diseases. As part of the agreement, Affymetrix will fund creative research and clinical projects that could lead to new genomic applications on the GeneChip platform, as well as novel diagnostics and screening tests.

"This is an exciting time when genomics offers the promise of a deeper understanding of biology while at the same time improving the practice of medicine," said Joseph Nevins, Ph.D., director of the IGSP Center for Applied Genomics & Technology at Duke University. "By combining our research expertise with Affymetrix' high-throughput microarray technology, we have the opportunity to build on our prior work and develop gene expression profiles that characterize oncogenic pathways and define tumor phenotypes, which are important in determining clinical outcomes. At the same time, this can translate into improved clinical care and provide an important resource to enhance the use of microarray technology for all Duke investigators."

"Affymetrix is excited to be working with a leading research organization such as Duke University to help bring more effective personalized tests and therapies to market faster," said Gregg Fergus, senior vice president, Global Sales Operations at Affymetrix. "Together, we hope to accelerate clinical research, improve patient care and open the door to new genomic applications."

Affymetrix collaborates with academic institutions and patient advocacy groups through the company's translational medicine program to develop more effective treatments. Affymetrix GeneChip microarray technology helps researchers tailor treatments for individual patients by identifying and measuring the genetic information associated with complex diseases. The translational medicine program complements the Powered by Affymetrix(TM) program, which enables companies to license GeneChip technology to develop innovative microarray products. This custom-designed technology is being used in many applications, including diagnostics, forensics, animal, industrial and food testing.

About Affymetrix

Affymetrix scientists invented the world's first high-density microarray in 1989 and began selling the first commercial microarray in 1994. Since then, Affymetrix GeneChip(R) technology has become the industry standard in molecular biology research. Affymetrix technology is used by the world's top pharmaceutical, diagnostic and biotechnology companies as well as leading academic, government and not-for-profit research institutes. More than 1,300 systems have been installed around the world and nearly 3,000 peer-reviewed papers have been published using the technology. Affymetrix' patented photolithographic manufacturing process provides the most information capacity available today on an array, enabling researchers to use a whole-genome approach to analyzing the relationship between genetics and health. Affymetrix is headquartered in Santa Clara, Calif., with manufacturing facilities in Sacramento, Calif., and Bedford, Mass. The company maintains important sales and marketing operations in Europe and Asia and has about 1,000 employees worldwide. For more information about Affymetrix, please visit the company's Web site at www.affymetrix.com.

All statements in this press release that are not historical are "forward-looking statements" within the meaning of Section 21E of the Securities Exchange Act as amended, including statements regarding Affymetrix' "expectations," "beliefs," "hopes," "intentions," "strategies," or the like. Such statements are subject to risks and uncertainties that could cause actual results to differ materially for Affymetrix from those projected, including, but not limited to: risks of the Company's ability to achieve and sustain higher levels of revenue, higher gross margins, reduced operating expenses; uncertainties relating to technological approaches, manufacturing (including risks related to the Company's ability to achieve hoped-for manufacturing yields for certain array products, including the ability to identify and resolve manufacturing problems), product development (including uncertainties relating to commercial and technological success of the strategic alliance between Duke University and Affymetrix discussed in this press release); personnel retention; uncertainties related to cost and pricing of Affymetrix products; dependence on collaborative partners; uncertainties relating to sole source suppliers; uncertainties relating to FDA and other regulatory approvals; competition; risks relating to intellectual property of others and the uncertainties of patent protection and litigation. These and other risk factors are discussed in Affymetrix' Form 10-K for the year ended December 31, 2004, and other SEC reports, including its Quarterly Reports on Form 10-Q for subsequent quarterly periods. Affymetrix expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in Affymetrix' expectations with regard thereto or any change in events, conditions or circumstances on which any such statements are based.

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