1. From the Department of Human Genetics (C.M.K.), University of Pittsburgh, Pittsburgh, Pa; the Southwest Foundation for Biomedical Research (C.M.K., D.L.R., L.A.C., J.L.S., M.C.M., J.R., J.L.V.), San Antonio, Tex; and the Southwest National Primate Research Center (J.R., J.L.V.), San Antonio, Tex.