Charles River Collaborates with Medical College of Wisconsin For Consomic Rat Models Used in Applied Genomics Research.

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WILMINGTON, Mass. & MILWAUKEE--(BW HealthWire)--Sept. 27, 2001

Charles River Laboratories International, Inc. (NYSE: CRL) and the Medical College of Wisconsin in Milwaukee today announced that the organizations have entered into an agreement to distribute novel "consomic" rat models developed at the Medical College through a special breeding program. These unique animal models will allow researchers to study the specific function of particular genes that contribute to common multigenic human diseases of the heart, lung and blood.

Charles River will exclusively produce and distribute the consomic rat models developed by the Medical College as well as provide other critical support services such as cryopreservation and rederivation. Five consomic strains currently exist and these will begin to be made available to the research community later this year and numerous additional strains will be developed by MCW over the next several years.

Consomic research models are generated by substituting whole chromosomes one at a time in each of the rat strains. This allows the contribution of genes on each chromosome to be studied in the laboratory for the particular traits of interest. These traits include conditions such as hypertension, myocardial infarction and renal disease. The end result of the chromosome substitution process developed at the Medical College is a rat model directed toward understanding and treating a particular disease condition from a gene function perspective, or pharmacogenomics. In addition, these rat strains allow gene identification much more rapidly.

The funding for the research and development of the consomic rat models at the Medical College, known as PhysGen, is one of eleven funded Programs for Genomic Applications (PGA) funded by the NIH's National Heart, Lung and Blood Institute (NHLBI). An initial funding of the project was from the Merck Genome Research Institute. An overview of the total PGA program, with links to individual programs, is available at: http://www.nhlbi.nih.gov/resources/pga/.

"PhysGen is likely to be the first high throughput physiology center in the world and our ability to collect over 200 heart, lung and blood traits in each strain offers unprecedented knowledge related to systems biology," said Allen Cowley, Jr., Ph.D., director of the Phenotyping Component of PhysGen and chairman of the department of physiology at the Medical College.

Data are available to the research community online at: http://pga.mcw.edu Howard Jacob, Ph.D., a longtime leader in the field of rat genetics, is the program director of PhysGen and Director of the Human and Molecular Genetics Center at the Medical College. "We expect the transfer of these technologies and resources to have a big impact on the research community and we're pleased to be able to collaborate with Charles River to deliver these resources," said Dr. Jacob. Charles River will utilize its existing facilities, scientific staff and worldwide distribution network to ensure that the models developed at the Medical College are widely available to the biomedical research community.

Charles River has long been regarded as the world's leading supplier of animal research models to the global research community, particularly for use in drug discovery and development. The Company has recently focused its technology development initiatives in the area of unique transgenic and cloned rat models that enable researchers to more efficiently investigate, discover and develop new treatments for human and animal diseases.

"We're delighted to be working with the Medical College of Wisconsin and Dr. Jacob in this new and very exciting area of consomic rat models directed to applied genomics research," commented James C. Foster, Chairman & CEO. "We expect the world class science being conducted at the Medical College by Dr. Jacob and colleagues, with the financial support of the NHLBI to lead to significant advances in understanding the genetic contribution to common diseases of the heart, lung, kidneys and blood. It's particularly rewarding to be able to direct our expertise, resources and capabilities to supporting scientific leaders focused on applied or functional genomics, as we move from identifying and mapping genes to actually understanding the contribution of genes in the disease process, beginning with predictive animal models."

The Medical College of Wisconsin in Milwaukee is the state's only private, freestanding medical and graduate school. Founded in 1893, it is dedicated to leadership and excellence in education, patient care, research and service. More than 1,400 students are enrolled in academic programs at the Medical College leading to the M.D., Ph.D., M.S., M.P.H., and M.A. degrees. Medical College faculty physicians provide care annually in every specialty of medicine to approximately 250,000 patients. Last year, its 900 faculty physicians and scientists received approximately $82 million in federal and private grants to conduct more than 1,500 medical research studies.

Charles River Laboratories, based in Wilmington, Massachusetts, is a leading provider of critical research tools and integrated support services that enable innovative and efficient drug discovery and development. The Company is the global leader in providing the animal research models required in research and development for new drugs, devices and therapies. The Company also offers a broad and growing portfolio of biomedical products and services that enable customers to reduce cost, increase speed, and enhance productivity and effectiveness in drug discovery and development. Charles River's customer base spans over 50 countries, and includes all of the major pharmaceutical and biotechnology companies, as well as many leading hospitals and academic institutions. The Company operates 75 facilities in 15 countries worldwide.

This document contains "forward looking statements." Such statements involve a number of risks and uncertainties that could cause actual results to differ materially from those stated or implied by the forward looking statements, including acquisition integration risks, special interest groups, contaminations, industry trends, new displacement technologies, outsourcing trends, USDA and FDA regulation, changes in law, special interests groups, continued availability of products and supplies, personnel and control, and others that are described in the Risk Factors contained in the Company's Registration Statement on Form S-3, as filed on July 19, 2001. The Company disclaims any intent or obligation to update forward looking statements, and otherwise claims the safe harbor protections for forward looking statements afforded under The Private Securities Litigation Reform Act of 1995.