Affymetrix 500K Array Used to Identify Memory Gene.

Discovery by TGen Researchers May Shed Light on Devastating Memory-Based Diseases Such as Alzheimer's and Parkinson's

SANTA CLARA, Calif. -- Affymetrix Inc. (Nasdaq:AFFX) announced today that researchers at the Translational Genomics Research Institute (TGen) in Phoenix, Arizona have used the Affymetrix 500K Array to discover a gene Co called Kibra Co associated with memory performance in humans. The team's findings may be used to develop new medicines for memory-based diseases such as Alzheimer's and Parkinson's by providing scientists with a better understanding of how memory works at the molecular level.

The study entitled, "Common KIBRA alleles are associated with human memory performance," will be published in the Oct. 20, 2006 issue of Science. The research team was led by Dietrich Stephan, Ph.D., director of TGen's Neurogenomics Division. It included colleagues at the University of Zurich in Switzerland, Banner Alzheimer's Institute and Mayo Clinic Scottsdale.

"Using the latest Affymetrix 500K Array, we have shed light on the fundamental biological process of human memory performance," said Dr. Stephan. "We can use this new understanding to develop drugs that will improve memory function."

Until now, researchers did not have access to the high-density technology needed to examine the genetic components associated with memory performance. The team at TGen used Affymetrix Human Mapping 500K Arrays to analyze 500,000 DNA markers simultaneously, providing a genetic blueprint for the memory-study participants. The researchers discovered the Kibra gene by comparing the genetic blueprints of people with good memory vs. poor memory and looking for the genetic variations consistently present in one group, but not the other. They then validated their discovery by replicating the Kibra gene finding in two separate and distinct groups of subjects.

"This memory study is a perfect example of how the use of advanced technologies in human genetics yields fundamental discoveries," said Stephen P.A. Fodor, Ph.D., chairman and CEO at Affymetrix.

To learn more about this breakthrough:

* Register for the upcoming Affymetrix Microarray Bulletin (AMB) teleconference/online symposium with Dr. Stephan on November 1, by visiting: http://www.microarraybulletin.com/memory_symposium

* Watch a full AMB interview featuring Dr. Stephan at http://www.microarraybulletin.com/memory

* Read an AMB interview with co-authors Dr. Stephan and Dr. David Craig, associate investigator and faculty member within the TGen Neurogenomics Program, at http://www.microarraybulletin.com/memory

* View the AMB graphic workflow (poster print-out) of the memory study at http://www.microarraybulletin.com/memory

About Translational Genomics Research Institute

The Translational Genomics Research Institute (TGen), a non-profit 501(c)(3) organization, is focused on developing earlier diagnostics and smarter treatments. Translational genomics research is a relatively new field employing innovative advances arising from the Human Genome Project and applying them to the development of diagnostics, prognostics and therapies for cancer, neurological disorders, diabetes and other complex diseases. TGen's research is based on personalized medicine and the institute plans to accomplish its goals through robust and disease-focused research.

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 1,400 systems have been installed around the world and more than 7,000 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 1,100 employees worldwide. For more information about Affymetrix, please visit the company's website 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 and uncertainties associated with the use of the Affymetrix 500K Array discussed in this press release; 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, 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/A for the year ended December 31, 2005, 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.