1. Division of Intramural Population Health Research; Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health; Bethesda Maryland
2. Division of Genetics; Wadsworth Center, New York State Department of Health; Albany New York
3. Congenital Malformations Registry; New York State Department of Health; Albany New York
4. Department of Epidemiology and Biostatistics; University at Albany School of Public Health; Rensselaer New York
5. Department of Epidemiology; College of Public Health, The University of Iowa; Iowa City Iowa
6. Genome Technology Branch; National Human Genome Research Institute, National Institutes of Health; Bethesda Maryland