1. Departments of Human Genetics (E.V.), Los Angeles, California 90095
2. Pediatrics (E.V., E.R.B.M.), University of California School of Medicine, Los Angeles, California 90095
3. Service de Génétique Médicale, Hôpital Necker-Enfants Malades (M.L.M., P.M.), Paris, France
4. Service de Pédiatrie, Hôpital Charles Nicolle (C.L.), Rouen, France
5. Service de Biologie, Hôpital Val-de-Grâce (F.D.), Paris, France
6. the Department of Pediatrics and Genetics, Stanford University Medical School (M.A.K.), Stanford, California