1. Department of Epidemiology; University of North Carolina; Chapel Hill NC USA
2. Carolina Population Center; University of North Carolina; Chapel Hill NC USA
3. Carolina Center for Genome Sciences; University of North Carolina; Chapel Hill NC USA
4. Department of Nutrition; University of North Carolina; Chapel Hill NC USA
5. Center for Applied Genomics; Children's Hospital of Philadelphia; Philadelphia PA USA
6. Department of Pediatrics; Children's Hospital of Philadelphia, Research Institute; Philadelphia PA USA
7. Department of Genetics; University of North Carolina; Chapel Hill NC USA
8. Department of Sociology; University of North Carolina; Chapel Hill NC USA