1. Laboratories of Pediatric Endocrinology (G.A., J.d.R., T.V., C.R.-S.), Academic Medical Center, University of Amsterdam, 1100 DD Amsterdam, The Netherlands
2. Genetic Metabolic Diseases (W.K., H.O., A.v.C.), Academic Medical Center, University of Amsterdam, 1100 DD Amsterdam, The Netherlands
3. Department of Pediatric Endocrinology (M.C.), Ghent University Hospital, B-9000 Ghent, Belgium