1. Department of Pediatrics; University of Iowa; Iowa City; Iowa
2. Department of Medical Genetics; Mayo Clinic; Rochester; Minnesota
3. Departments of Microbiology and Molecular Genetics; Pediatrics and Human Development; Michigan State University; East Lansing; Michigan
4. Center for Craniofacial and Dental Genetics, Department of Oral Biology; School of Dental Medicine, Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh; Pittsburgh; Pennsylvania