1. Department of Pediatrics University of Wisconsin School of Medicine and Public Health Madison Wisconsin USA
2. Department of Pediatrics McGovern Medical School at UT Health Houston Texas USA
3. Department of Pediatrics A. l. duPont Hospital for Children, Thomas Jefferson University Wilmington Delaware USA
4. Department of Genetics Children's Wisconsin; Medical College of Wisconsin Milwaukee Wisconsin USA
5. Department of Epidemiology Johns Hopkins University Baltimore Maryland USA
6. Greenberg Center for Skeletal Dysplasias, McKusick Nathans Department of Genetic Medicine Johns Hopkins University Baltimore Maryland USA