1. Department of Epidemiology and Biostatistics; Arnold School of Public Health; University of South Carolina; Columbia South Carolina
2. Division of Intramural Population Health Research; Eunice Kennedy Shriver National Institute of Child Health and Human Development; National Institutes of Health; Bethesda Maryland
3. Department of Health; Division of Genetics; Wadsworth Center; Albany New York
4. Department of Laboratory Medicine and Pathology; University of Minnesota Medical School; Minneapolis Minnesota
5. Department of Health; Congenital Malformations Registry; Albany New York
6. University at Albany School of Public Health; Rensselaer New York
7. Department of Epidemiology; College of Public Health; The University of Iowa; Iowa City Iowa
8. Genome Technology Branch; National Human Genome Research Institute; National Institutes of Health; Bethesda Maryland