1. Departments of Nephrology (B.B., H.P.H.N.) D 79106 Freiburg, Germany
2. Departments of Endocrinology (A.-C.K., M.F., B.A.) D 97070 Würzburg, Germany
3. Dermatology (J.S.), Julius-Maximilians-University, D 97070 Würzburg, Germany
4. Laboratory Medicine (M.M.H.), Albert-Ludwigs-University, D 79106 Freiburg, Germany
5. Genomic Medicine Institute (C.E.), Cleveland Clinic Foundation, Cleveland, Ohio 44195; and Department of Genetics, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106