Affymetrix Hosts Pharmacogenetics Workshop at Discovery 2 Diagnostics Conference

Affymetrix Inc. (Nasdaq:AFFX) announced today that it is hosting a "Pharmacogenetics, Clinical Development and Tailored Therapies” workshop at the Discovery 2 Diagnostics Conference in Philadelphia. The workshop will focus on how researchers can use genetic information to improve drug development and will include new information on using the SNP Array 6.0 to discover unknown investigative biomarkers, as well as the DMET Panel to directly assay valid biomarkers of drug metabolism. What: Pharmacogenetics, Clinical Development and Tailored Therapies Where: Room 113C in the Pennsylvania Convention Center When: Monday, September 17, 2007 at 1:50pm EDT For more information on the workshop: www.microarraybulletin.com/d2d2007 "We’ve worked with our pharmaceutical partners to develop distinct pharmacogenetic solutions depending on the question being asked in drug development,” said Tommy Broudy, Ph.D., senior manager of marketing for pharmacogenetics at Affymetrix. "For instance, if you have an adverse response of unknown causes, then the whole-genome approach makes great sense. However, if you have a drug metabolism issue, the only way to assay all of the clinically relevant biomarkers in known genes like CYP2D6 is to use the DMET Panel.” The workshop features guest speaker, Michael D. Caldwell, M.D., Ph.D., director of the Wound Healing Program at Marshfield Clinic, who will discuss warfarin pharmacogenetics, existing biomarkers for predicting stable dosage and current investigations for discovery and validation of new biomarkers. Affymetrix and the Marshfield Clinic have been collaborating on a large clinical genotyping project designed to discover genetic variations associated with stable warfarin dosing. Additionally, Affymetrix is hosting a second workshop at the D2D conference focused on the discovery and validation of gene expression biomarkers in FFPE samples. Historically, FFPE samples have been unusable for microarray studies because of poor RNA quality in the preserved tissue. Recent developments in RNA extraction and target preparation assays now enable scientists to use FFPE samples for gene expression studies, such as cancer classification. This approach accelerates clinical studies by enabling the use of retrospective samples. For information on the workshop visit: www.microarraybulletin.com/d2d2007. About Affymetrix Pharmacogenetic Solutions The SNP Array 6.0 interrogates more than 1.8 million markers of common genetic variation, enabling pharmaceutical researchers to scan the genome and discover associations between unknown biomarkers and safety, efficacy or adverse events. The DMET Panel directly assays more than 1,000 genetic variations in more than 150 drug metabolism genes, enabling pharmaceutical researchers to quickly and comprehensively understand the genetic basis of pharmacokinetic issues. The DMET assay includes variants that the U.S. FDA refers to as valid biomarkers known to impact drug metabolism. About Affymetrix Affymetrix GeneChip® microarray technology is the industry-standard tool for analyzing complex genetic information. After inventing microarray technology in the late 1980s, Affymetrix scientists have been dedicated to developing innovative products that provide researchers with a more complete view of the genome. These products continue to accelerate genetic research and enable scientists to develop diagnostics and tailor treatments for individual patients by identifying and measuring the genetic information associated with complex diseases. Today, 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 1,600 systems have been shipped around the world and more than 9,500 peer-reviewed papers have been published using the technology. Affymetrix is headquartered in Santa Clara, Calif., and has manufacturing facilities in Sacramento, Calif., and Singapore. The company has about 1,100 employees worldwide and maintains sales and distribution operations across Europe and Asia. For more information about Affymetrix, please visit the company’s website at www.affymetrix.com. Forward-looking Statements 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 and uncertainties associated with this press release; risks of the company’s ability to achieve and sustain higher levels of revenue, higher gross margins and reduced operating expenses; uncertainties relating to technological approaches, manufacturing and product development; 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, 2006, 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.