Personalized Medicine Coalition Announces Two New Board Members

— Respected Leaders in the Diagnostics Industry Add to Depth and Breadth of PMC Board —

Washington, DC - July 23, 2008 —

The Personalized Medicine Coalition (PMC) today announced the appointment of Pierre G. Cassigneul, president and chief executive officer of XDx, Inc., and David P. King, chief executive officer, president and director of Laboratory Corporation of America® Holdings (LabCorp®) (NYSE: LH), to its Board of Directors. The PMC, an educational and advocacy group dedicated to advancing the understanding and adoption of personalized medicine, was launched in 2004 by more than 15 leading pharmaceutical, biotechnology, diagnostics, and information technology companies, as well as major academic centers and governmental agencies, and now includes over 140 members representing all the stakeholders with an interest in personalized medicine.

"We have been very fortunate over the last five years to have a Board of Directors that consists of highly respected individuals who are actively reshaping the face of healthcare," said Edward Abrahams, Executive Director of the PMC. "Pierre Cassigneul and David King are no exception, and both will be tremendous assets to our Board. Their combined expertise in the diagnostics industry and passion about our mission will greatly assist the PMC’s efforts to create a friendlier landscape for personalized medicine."

Cassigneul, chief executive officer and president of XDx, Inc., has more than 20 years of international senior management experience in the healthcare and medical device industries, including the launch of several successful high-tech products. XDx, a molecular diagnostics company, is one of the first companies to develop and commercialize practical applications built on insights from the Human Genome Project. Before joining XDx, Cassigneul served in top management positions at Stone Bridge Management LLC, Becton Dickinson & Co., Bayer, Ortho Diagnostics Systems (J&J) and Abbot Laboratories. Cassigneul holds a management degree from the Ecole Superieure de Commerce de Reims in France.

"I am honored to join the Board of the PMC," said Cassigneul. "For providers of products and services to be able to deliver on the promise of personalized medicine, policymakers must intelligently and comprehensively review the array of issues that affect the science and clinical practice of personalized medicine. PMC is uniquely positioned to address these issues and ensure a coherent, integrated approach to the legal, financial, social and professional issues that will shape the development and application of personalized medicine."

Also joining is David P. King, chief executive officer, president and director of Laboratory Corporation of America Holdings (LabCorp). A pioneer in genomic testing and the commercialization of new diagnostic technologies, LabCorp is one of the world’s largest clinical laboratories. Prior to becoming chief executive officer in 2007, King served as LabCorp’s executive vice president of strategic planning and corporate development and chief operating officer since 2005. King’s career at LabCorp followed a distinguished legal career from 1992 to 2001 as a partner at Hogan & Hartson, L.L.P., where he served as LabCorp’s outside counsel. King holds an AB degree from Princeton University and a JD degree from the University of Pennsylvania Law School.

"I look forward to working with the rest of the Board to advance PMC’s efforts to influence critical policy decisions in the coming years," King said. "PMC is the only organization that brings together thought leaders from every part of the healthcare industry to explore critical issues that will impact the future of medicine. LabCorp is proud to assist PMC's efforts to promote the emergence of personalized medicine as a critical part of the future of healthcare."

About the Personalized Medicine Coalition
The Personalized Medicine Coalition (PMC), representing a broad spectrum of academic, industrial, patient, provider, and payer communities, seeks to advance the understanding and adoption of personalized medicine concepts and products for the benefit of patients. For more information on the Personalized Medicine Coalition, please visit www.PersonalizedMedicineCoalition.org.

About XDx, Inc.
Based in Brisbane, California, XDx is a molecular diagnostics company focused on the discovery, development and commercialization of noninvasive gene expression-based tests for the monitoring of transplant rejection and autoimmune diseases. The company has developed a proprietary new method for noninvasively monitoring immune system activity by measuring gene expression in a patient’s peripheral blood. This work is the basis for AlloMap molecular expression testing, which provides transplant physicians with a new tool to aid in the identification of the probability of acute cellular rejection for postcardiac transplant patient management. Some of the AlloMap molecular expression technology developed and implemented by XDx in heart transplant patient management may be applicable to other diseases that involve transplant rejection and the immune system. XDx’s noninvasive technology offers the potential to decrease healthcare costs and significantly improve the quality of life for patients with a variety of life-threatening or life-altering immune-mediated diseases. For more information on XDx, please visit the company’s website at www.xdx.com.

About LabCorp®
Laboratory Corporation of America® Holdings, a S&P 500 company, is a pioneer in commercializing new diagnostic technologies and the first in its industry to embrace genomic testing. With annual revenues of $4.1 billion in 2007, over 26,000 employees nationwide, and more than 220,000 clients, LabCorp offers clinical assays ranging from routine blood analyses to HIV and genomic testing. LabCorp combines its expertise in innovative clinical testing technology with its Centers of Excellence: The Center for Molecular Biology and Pathology, National Genetics Institute, Inc., ViroMed Laboratories, Inc., The Center for Esoteric Testing, DIANON Systems, Inc., US LABS, and Esoterix and its Colorado Coagulation, Endocrine Sciences, and Cytometry Associates laboratories. LabCorp conducts clinical trial testing through its Esoterix Clinical Trials Services division. LabCorp clients include physicians, government agencies, managed care organizations, hospitals, clinical labs, and pharmaceutical companies. To learn more about our organization, visit our Web site at: www.labcorp.com.

Contact:
Edward Abrahams, Executive Director, Personalized Medicine Coalition
(202) 589-1770

Eric Lindblom, Laboratory Corporation of America
(336) 436-6739

Sheryl Seapy, Pure Communications
(949) 608-0841