1. Clinical Endocrinology Branch, National Institute of Diabetes and Digestive and Kidney Disease, National Institutes of Health, Bethesda, Maryland.
2. Division of Cardiovascular Sciences, National Health, Lung, and Blood Institute, Bethesda, Maryland.
3. Biostatistics, Jackson State University, Jackson, Mississippi.
4. School of Nursing, University of Mississippi Medical Center, Jackson, Mississippi.
5. Department of Medicine, University of Mississippi Medical Center, Jackson, Mississippi.
6. Center for Research on Genomics and Global Health, National Human Genome Research Institute, Bethesda, Maryland.