1. Shriner's Hospital for Crippled Children, 3101 SW Sam Jackson Park Rd, Portland, OR 97201, U.S.A.
2. Orthopedic Surgery, National Beppu Hospital, Oita, Japan
3. Laboratory of Developmental Biology and Anomalies, National Institute of Dental Research, National Institutes of Health, Bethesda, MD 20892, U.S.A.