1. Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Madrid, Spain
2. Department of Pediatrics, Universidad Autónoma de Madrid; Madrid, Spain
3. CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, Madrid, Spain
4. Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA, USA
5. Institute of Normal Human Morphology, University of Ancona, Ancona, Italy
6. Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK
7. Metabolic Disease Group, The Wellcome Trust Sanger Institute, Hinxton, UK
8. UPMC Univ Paris 06, UMR_S938, Paris, France
9. INSERM, UMR_S938, Faculté de Médecine Pierre et Marie Curie, Site Saint‐Antoine, Paris, France
10. AP‐HP, Hôpital Tenon, Service de Biochimie et Hormonologie, Paris, France
11. Wellcome Trust Clinical Research Facility, Addenbrooke's Hospital, Cambridge, UK
12. Multi‐imaging Centre, Physiology Development & Neuroscience, University of Cambridge, Cambridge, UK
13. Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Oxford, UK
14. Institute of Biomedical and Clinical Science (AM.P.), Peninsula Medical School, Exeter, UK
15. Division of Nutrition and Metabolic Diseases, Department of Internal Medicine, Center for Human Nutrition, University of Texas Southwestern Medical Center at Dallas, Dallas, TX, USA