1. Department of Medical Genetics, University of Wisconsin, Madison, WI 53706.
2. Department of Medical Genetics, University of Wisconsin, Madison, WI 53706 and Shodair Children's Hospital, Helena, MT 59604.
3. Department of Medical Genetics, University of Wisconsin, Madison, WI 53706 and University of Chicago Genetic Services, Chicago, IL 60637.
4. Department of Medical Genetics, University of Wisconsin, Madison, WI 53706 and Perinatal Associates, Obstetrix Medical Group, Renton, WA 98055.
5. Department of Medical Genetics, University of Wisconsin, Madison, WI 53706 and Kaiser Permanente, Department of Genetics, Clackamas, OR 97015