AMBION AND CENIX BIOSCIENCE ANNOUNCE AVAILABILITY OF
PRE-DESIGNED siRNAS COVERING THE HUMAN, MOUSE AND RAT GENOMES

Austin, TX, USA and Dresden, Germany – August 26, 2003. Ambion, Inc. and Cenix BioScience GmbH, both leaders in the RNAi market, announced today that siRNA designs are now complete for more than 98% of all human, mouse, and rat genes listed in the public RefSeq database. These siRNAs promise to be the best new tool for fulfilling the promise of the Human Genome Project by enabling the efficient identification and functional characterization of novel disease-relevant genes.

The siRNA designs were created using a proprietary algorithm developed by Cenix that predicts potent and specific siRNA sequences with a high degree of accuracy. This algorithm utilizes Cenix’s expertise gained from generating genome-wide RNAi libraries for C. elegans and Drosophila, plus extensive testing in mammalian cell systems. The efficacy of the optimized siRNA design algorithm was tested on multiple siRNAs per gene, targeting hundreds of different genes. These pre-designed siRNAs are now being offered to the research community, eliminating the need for individual researchers to deal with complicated siRNA design tools and allowing them to rapidly obtain multiple siRNAs for each gene of interest.

Ambion is commercializing these designs by offering chemically synthesized siRNAs corresponding to each design both individually and as pre-defined libraries. Ambion has established high throughput manufacturing capacity necessary to produce thousands of siRNAs of the highest quality to serve the research market. The company also has the ability to synthesize gram quantities of siRNA under ISO and cGMP standards.

Matt Winkler, CEO and CSO of Ambion, commented, “The power of these pre-designed siRNAs is that it permits all researchers to perform siRNA experiments immediately. RNAi is revolutionizing the pace of basic biological research, from the dissection of signaling pathways to the detailed determination of gene function.”

“The availability of these pre-designed siRNAs greatly reduces the research community’s barrier of entry for genome-scale RNAi experimentation in mammalian cells,” Christophe Echeverri, CEO of Cenix BioScience stated. “We are particularly excited to finally address the numerous requests we have received over the last year for these powerful reagents from both academic and industry laboratories.”

Cenix BioScience offers premium research services specializing in genome-based high throughput applications of RNA-mediated interference (RNAi). Founded in 1999 from pioneering work in RNAi screening, Cenix combines high content analyses with proprietary genome-wide RNAi libraries for use in key experimental systems including human cells, Drosophila and C. elegans. Cenix is now making its unique expertise accessible to academic and industry researchers through a wide range of fully customized research services. Please visit the company’s web site www.cenix-bioscience.com for more information.

Ambion, Inc., is a leader in the development and supply of innovative RNA-based life science research and molecular diagnostic products. Ambion has taken a leadership role in developing products for handling, preserving, isolating, detecting and measuring RNA in areas such as molecular biology, cell biology, microbiology, drug discovery and genomics. Ambion is also a leading supplier for RNAi products. For more information, please visit the company’s web site www.ambion.com.

RNA interference, or RNAi, is a powerful new approach for achieving targeted gene silencing of disease-associated genes using double stranded RNA (dsRNA) as the triggering agent. Discovered in 1998, this technology has been shown to work in a wide range of animal models, and was voted the top scientific achievement of 2002 by Science Magazine. RNAi is a naturally occurring, highly catalytic gene regulation system, thought to have evolved primarily as a defense mechanism against molecular pathogens. Used as a research tool and potential therapeutic, RNAi offers an unprecedented combination of:
1) High potency, specificity and scalability,
2) Wide cross species applicability,
3) Excellent experimental reproducibility.
As a result, RNAi has rapidly become the new method of choice, replacing conventional antisense and ribozyme technologies, to determine gene functions for a wide range of biomedical applications.

Contacts:
David Dorris	Ellen Fuerst
Business Development Manager	Public Relations
Ambion, Inc.	Cenix BioScience GmbH
Tel: +1 512-651-0200	Tel: +49 (0) 351 210-2511
Bruce Leander	Dr. Christophe Echeverri
President	CEO/CSO
Ambion, Inc.	Cenix BioScience GmbH
Tel: +1 512-651-0200	Tel: +49 (0) 351 210-1300