1. Endocrinology Unit, Department of Pediatrics (A.M.-A., A.R., A.C.)
2. School of Medicine (N.R.), Pontificia Universidad Católica de Chile, 833-0074, Santiago, Chile
3. Department of Radiology and Pediatrics (C.G., R.P.)
4. Molecular Biology Laboratory (M.L., L.V., H.P.), Pontificia Universidad Católica de Chile, 833-0074, Santiago, Chile