1. Division of Nutrition and Metabolic Diseases (K.N.J., A.K.A., A.G.), Department of Internal Medicine, and the Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, Texas 75390;
2. Endocrinology Unit (F.B.), Santa Maria Hospital, 1649-035 Lisbon, Portugal;
3. Medical Genetics Service (H.G.d.S.), 1649-035 Lisbon, Portugal;
4. Department of Pathology (J.O.), University of Washington, Seattle, Washington 98195