Jeff Milunsky M.D. is an Assistant Professor of Pediatrics at Boston University School of Medicine (BUSM), interested in the molecular genetic study of hearing loss. He is Board-certified in Pediatrics, Clinical Genetics, and Clinical Molecular Genetics, and has established a Genetics Deafness Clinic at Boston Medical Center in conjunction with Otolaryngology. His research to date includes investigations of Connexin- 26, mitochondrial deafness, Paraganglioma, and the Carney Complex. An immediate short-term goal is to learn and master new molecular technologies. The long-term goal is to continue as a full-time academic researcher, become established as an independent investigator with a laboratory, and solidify a career in patient- oriented research. The career development plan involves frequent mentor meetings, seminars, formal training in genetic technology (Mass Spect. and DNA microarrays) and the responsible conduct of research, as well as attending and participating in National meetings. Clinton Baldwin PhD is an Associate Professor of Pediatrics and Director of Molecular Genetics Research at the Center for Human Genetics at BUSM and will serve as mentor to Jeff Milunsky M.D. for the proposed K23 award. Dr. Baldwin has a long-term interest in human genetics and has cloned or mapped several deafness genes including Pax3 in WS1. The research will be performed at the Center for Human Genetics, which has state-of-the-art molecular genetics facilities including ABI and Li-Cor gene sequencers, Biomek robotic work-stations, Mass Spectrometry for DNA analysis and Microarray chip technology. The research project is to identify additional Waardenburg Syndrome type 2 (WS2) loci in man. WS is one of the most common autosomal dominant syndromes responsible for about 3% of congenital hearing loss. We will perform a high-density genome scan coupled with linkage disequilibrium analyses on 3 large multigenerational families and multiple smaller families with WS2 to identify candidate gene(s) with mutations causing WS2.