SAN DIEGO-June 29, 2005- Investigators from the University California, San Diego (UCSD) Branch of the Ludwig Institute for Cancer Research (LICR) and NimbleGen Systems have developed an efficient method to identify thousands of regulatory sequences in the human genome, according to a study published online today in Nature.

Genes are defined by their ability to generate a functional product. Thus the 'promoter' - a DNA sequence that controls when and where a gene product is generated - is the critical element that distinguishes a gene from 'junk DNA.' Using a set of NimbleGen's DNA microarrays that represent the entire human genome, the team was able to track critical proteins binding to each gene's promoter to identify 10,567 active promoters, 5449 of which were previously unknown.

LICR's Dr. Bing Ren, the senior author of the study and a faculty member at the UCSD School of Medicine, says that although scientists have found most of the protein-coding genes in the human genome, their control sequences have been elusive until now. "Promoters are a type of genetic switch that turn gene expression on or off. If we know where the promoters are, we can study how the genetic switches work in a cell and investigate their connection to human diseases." Dr. Ren and his colleagues have made the data freely available on online public databases.

Dr. Robert Strausberg, Vice-President of Human Genomic Medicine at the J. Craig Venter Institute, says that this understanding is vital for determining the genetic causes of, and possible genomic solutions for, diseases such as cancer. "Medicine is increasingly turning towards the idea of using genetic markers for diagnosis and prognosis, or determining personalized therapies, so-called pharmacogenetics, but we don't know how these genes are regulated or even related to each other. The identification of such a large number of promoters means that we can begin to answer these sorts of questions."

The authors of this study were: Tae Hoon Kim, Leah O. Barrera and Chunxu Qu, University California, San Diego Branch of the Ludwig Institute for Cancer Research (La Jolla, CA); Ming Zheng, and Yingnian Wu, University California, Los Angeles Department of Statistics (Los Angeles, CA); Michael A. Singer, Todd Richmond and Roland D. Green, NimbleGen Systems, Inc (Madison, WI); and Bing Ren, University California, San Diego Branch of the Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine (in the UCSD) School of Medicine and Moores UCSD Cancer Center (La Jolla, CA).

Promoter data are available on the UCSC Genome Browser and the National Center for Biotechnology Information Gene Expression Omnibus

This publication may be found online at http://dx.doi.org/10.1038/nature03877.

The Ludwig Institute for Cancer Research (LICR) is the largest international academic institute dedicated to understanding and controlling cancer. With ten Branches in seven countries, and numerous Affiliates and Clinical Trial Centers in many others, the scientific network that is LICR quite literally covers the globe. The uniqueness of LICR lies not only in its size and scale, but also in its philosophy and ability to drive its results from the laboratory into the clinic. LICR has developed an impressive portfolio of reagents, knowledge, expertise, and intellectual property, and has also assembled the personnel, facilities, and practices necessary to patent, clinically evaluate, license, and thus translate, the most promising aspects of its own laboratory research into cancer therapies.

NimbleGen Systems, the leading supplier of flexible high-density microarray products and services, is enabling a new era of "High-Definition Genomics^SM." NimbleGen uniquely produces high-density arrays of isothermal long oligos that provide superior results for advanced genomic analysis methods such as CGH, ChIP, mutation mapping, re-sequencing, and expression tiling. NimbleGen's High-Definition Genomics enables scientists to obtain and integrate complex genetic data sets not previously accessible, providing a much clearer understanding of genomics and systems biology. This improved performance is made possible by NimbleGen's Maskless Array Synthesis (MAS) technology, which uses digital light processing and rapid, high-yield photo-deposition chemistry to synthesize DNA