AFFX Affymetrix, Inc.

Affymetrix Inc. (Nasdaq:AFFX) announced today that Korea's National Institute of Health (NIH) and Center for Disease Control and Prevention will use the Affymetrix GeneChip(R) Human Mapping 500K Array Set for a series of groundbreaking genome-wide association studies in critical disease areas, including diabetes, hypertension, asthma and metabolic syndrome. The Korean NIH will work with its academic and industry collaborators to generate more than 10 billion individual genotypes from 20,000 human DNA samples to help identify the genetic causes of these diseases. "Using the new high-throughput Affymetrix technology, we will perform genome-wide association studies to discover and understand the genes associated with a number of conditions that are unusually prevalent in Korea," said Kuchan Kimm, M.D., Ph.D and director of the Center for Genome Science at the National Institute of Health, Republic of Korea. "We feel these studies can improve the quality of life in Korea by helping us develop cost-effective therapeutics and personalized preventative measures against conditions such as diabetes, hypertension and metabolic syndrome." Until recently, scientists have had a difficult time performing whole-genome association studies in complex diseases because the technology was limited to viewing a few thousand markers at a time. The Affymetrix GeneChip Human Mapping 500K Array Set provides a more comprehensive view, enabling researchers to analyze 500,000 markers simultaneously and perform whole-genome analyses in large populations for the first time. "Whole-genome association studies are accelerating genetic discoveries in labs around the world," said Tom Willis, Ph.D, vice president of DNA Marketing at Affymetrix. "The GeneChip Human Mapping 500K Array Set is quickly becoming the standard in large-scale genotyping, enabling researchers to understand at last the underlying causes of complex diseases. When combined with our targeted genotyping products, our GeneChip platform will allow discoveries to be validated efficiently and brought to the patient's bedside, where new treatments and tests will allow the promise of personalized healthcare to be realized." Researchers using the Affymetrix GeneChip Human Mapping products have demonstrated the power of this approach through significant early discoveries in diseases such as macular degeneration, cardiovascular disease, inflammatory disease and cancer. More than 60 researchers are using the GeneChip Human Mapping 500K Array Set, and more than 20 of their studies involve at least 1,000 patients. About Affymetrix Affymetrix scientists invented the world's first 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 by leading academic, government and not-for-profit research institutes. More than 1,300 GeneChip systems have been shipped around the world and more than 4,000 peer-reviewed papers have been published using the technology. Affymetrix' patented photolithographic manufacturing process provides the highest information capacity available today on an array, enabling researchers to use a whole-genome approach to analyze 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 (including risks associated with the Company's ability to achieve hoped for revenue targets for the GeneChip Human Mapping 500K Array Set), 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 the Korea NIH 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 Dec. 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. NOTE: Affymetrix, the Affymetrix logo and GeneChip are registered trademarks owned or used by Affymetrix Inc.