1. Clinical and Molecular Epidemiology Unit, Department of Hygiene and Epidemiology, University of Ioannina School of Medicine, Ioannina 45110, Greece;
2. Department of Internal Medicine, Department of Human Genetics, and Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan 48109;
3. Divisions of Endocrinology and Genetics and Center for Basic and Translational Obesity Research, Boston Children's Hospital; Department of Genetics, Harvard Medical School; and Program in Medical and Population Genetics, Broad Institute, Boston, Massachusetts 02115;
4. Stanford Prevention Research Center, Department of Medicine, Department of Health Research and Policy, and Department of Statistics, Stanford University, Stanford, California 94305;