Affymetrix and Qiagen to Collaborate on siRNA Research Using GeneChip® Technology

Affymetrix and Qiagen to Collaborate on siRNA Research Using GeneChip® Technology

-- Affymetrix’ whole-genome view will provide more complete picture of siRNA experiments --

Santa Clara, Calif. and Venlo, The Netherlands, Oct. 29, 2003 – Affymetrix, Inc., (NASDAQ: AFFX) and QIAGEN N.V. (Nasdaq: QGENF, Frankfurt, Prime Standard: QIA) today announced that they have entered into a collaboration to optimise QIAGEN siRNA-mediated gene silencing using Affymetrix GeneChip® microarray technology. The collaboration is intended to develop optimised procedures that can be standardized to analyse gene silencing effects on a genome-wide basis.

QIAGEN has a leading position in gene silencing by siRNA using synthesis technology based on a proprietary chemistry (TOM amidites), and on transfection methods and kits for introduction of siRNA into target cells. The ability of market leading Affymetrix GeneChip expression arrays to provide a comprehensive picture of all the protein-coding content in the human genome enables researchers to determine on a whole genome scale, on- and off-target effects of siRNA-mediated gene silencing.

Optimised protocols and data resulting from the collaboration describing the benefits of using the two technologies together will be provided to researchers in technical notes.

“Use of siRNA as a tool to impact important biological pathways is a rapidly growing area of research in basic biology and therapeutic development,” said Trevor J. Nicholls, Ph.D., Affymetrix’ Chief Commercial Officer. “The whole-genome view that Affymetrix arrays offer will give researchers a more complete understanding of the downstream effects of siRNAs in their experiments and clinical research. We are pleased to be working with QIAGEN in this exciting area. This relationship complements our recently announced collaboration with PreAnalytiX GmbH to develop sampling protocols in clinical research.”

“This collaboration adds another cornerstone to the already existing partnerships with Affymetrix, said Dr. Ulrich Schriek, Vice President Corporate Business Development of QIAGEN. “It will strengthen QIAGEN’s presence in what has evolved to one of the most dynamic areas of today’s functional genomics market. The combination of our synthetic siRNA and transfection products with the market’s leading array technology will set new standards and is ideally suited to provide an optimal tool set to researchers studying complex genetic pathways and networks.”

About Affymetrix:

Affymetrix is a pioneer in creating breakthrough tools that are driving the genomic revolution. By applying the principles of semiconductor technology to the life sciences, Affymetrix develops and commercializes systems that enable scientists to improve the quality of life. The Company's customers include pharmaceutical, biotechnology, agrichemical, diagnostics and consumer products companies as well as academic, government and other non-profit research institutes. Affymetrix offers an expanding portfolio of integrated products and services, including its integrated GeneChip platform, to address growing markets focused on understanding the relationship between genes and human health. Additional information on Affymetrix can be found at www.affymetrix.com.

About QIAGEN:

QIAGEN N.V., a Netherlands holding company with subsidiaries in Germany, the United States, Japan, the United Kingdom, Switzerland, France, Italy, Australia, Norway, Austria and Canada, believes it is the world's leading provider of innovative enabling technologies and products for the separation, purification and handling of nucleic acids. The Company has developed a comprehensive portfolio of more than 320 proprietary, consumable products for nucleic acid separation, purification and handling, nucleic acid amplification, as well as automated instrumentation, synthetic nucleic acid products and related services. QIAGEN's products are sold in more than 42 countries throughout the world to academic research markets and to leading pharmaceutical and biotechnology companies. In addition, the Company is positioning its products for sale into developing commercial markets, including DNA sequencing and genomics, nucleic acid-based molecular diagnostics, and genetic vaccination and gene therapy. QIAGEN employs approximately 1,600 people worldwide. Further information on QIAGEN can be found at www.qiagen.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, product development, market acceptance, 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, 2002 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 and are registered trademarks owned or used by Affymetrix, Inc.