Ronald J Jorgenson1, M Elbert Cocker2. 1. The Johns Hopkins University, School of Medicine, Division of Medical Genetics, Baltimore, Maryland 21205, presently at College of Dental Medicine, Medical University of South Carolina, 80 Barre Street, Charleston, South Carolina 29401. 2. University of Texas at Houston, Dental Branch, Division of Periodontics, Houston, Texas 77025.