William Gahl, M.D., Ph.D., presents "Rare Diseases and the NIH Undiagnosed Diseases Program" at the 2009 Bridging ehe Translational Divides symposium hosted by the Einstein-Montefiore Institute for Clinical and Translational Research. Dr. Gahl is the clinical director of the National Human Genome Research Institute, senior investigator of the Medical Genetics Branch, and head of the Human Biochemical Genetics Section at the National Institutes of Health.