1. From the Departments of Genetics and Pediatrics, Yale University School of Medicine, New Haven, Connecticut; Riley Hospital for Children, Section of Pediatric Metabolism/Genetics, Indianapolis, Indiana;
2. Riley Hospital for Children, Section of Pediatric Metabolism/Genetics, Indianapolis, Indiana; Wesley Medical Center, Wichita, Kansas; the
3. Wesley Medical Center, Wichita, Kansas; and the University of Washington, Seattle, Washington;
4. Mental Retardation Program, National Institutes of Health, National Institute of Child Health and Human Development, Bethesda, Maryland. National PKU News, Seattle, Washington; and the
5. Departments of Genetics and Pediatrics, Yale University School of Medicine, New Haven, Connecticut.