Collaboration to Explore the Genetic Causes of Mental Retardation

SANTA CLARA, Calif.--(BUSINESS WIRE)--July 9, 2007--Affymetrix Inc. (Nasdaq:AFFX) today announced the launch of the European Cytogenetic Research Initiative, a collaboration between Affymetrix, the University of Nijmegen in the Netherlands, the University of Tuebingen in Germany and the NHS Regional Genetics Laboratory in Birmingham, U.K. The collaborators are using Affymetrix microarray technology to identify the specific causative mutations in mentally retarded children.

Currently, cytogeneticists use karyotyping and FISH technologies to understand how deletions, amplifications and other chromosomal rearrangements lead to congenital abnormalities and mental retardation in children. The Affymetrix microarray platform provides a higher-resolution view of the genome than traditional cytogenetic solutions, enabling researchers to better identify causative mutations, copy number variants and loss of heterozygosity (LOH) information.

"Each year up to 30,000 children with learning difficulties will be tested in the U.K. alone using karyotyping and targeted FISH methods, and these technologies are only helping to resolve 5 to 10 percent of cases," said Dominic McMullan, Ph.D., head of molecular cytogenetics, NHS Regional Genetics Laboratory.

"Affymetrix GeneChip(R) technology provides industry-leading copy number resolution and LOH information," said Olaf Riess, M.D., head of the department for medical genetics, University of Tuebingen. "With this technology, we expect to find a much higher number of causal de novo deletions and amplifications than we could with the current gold-standard methods like karyotyping."

"Our laboratory has extensive experience in using homemade 32K BAC arrays in the cytogenetic analysis of children with unexplained mental retardation," said Joris A. Veltman, Ph.D., head of the microarray facility, University of Nijmegen. "We selected the Affymetrix technology because the GeneChip SNP Array platform provides a higher-resolution view of copy number variations, enabling us to improve our cytogenetic efforts to better understand mental retardation."

"Affymetrix is pleased to partner with these three leading genetic research labs to demonstrate how our copy number products can improve cytogenetic analysis," said Marcus Hausch, Ph.D., senior marketing manager at Affymetrix. "Because it provides a higher-resolution view of the genome, the Affymetrix platform is uniquely positioned to become the gold-standard tool in cytogenetic research."

About Affymetrix

Affymetrix GeneChip(R) 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 1,500 systems have been shipped around the world and more than 8,500 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: 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 the outcome of the European Cytogenetic Research Initiative and the use of the Affymetrix technology discussed in 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(R) are registered trademarks owned or used by Affymetrix Inc.

CONTACT: Affymetrix Inc.
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SOURCE: Affymetrix Inc.