1. National Human Genome Research Institute (P.F.), National Institutes of Health, Bethesda, Maryland 20892
2. Clinical Center (K.C., S.H., T.S.), National Institutes of Health, Bethesda, Maryland 20892
3. National Institute of Dental and Craniofacial Research (P.G.R., M.T.C.), National Institutes of Health, Bethesda, Maryland 20892