1. Departments of Pediatrics (M.B., E.G., M.H., D.B.W.), Washington University School of Medicine, St. Louis Children’s Hospital, St. Louis, Missouri 63110
2. Molecular Biology and Pharmacology (I.B., D.B.W.), Washington University School of Medicine, St. Louis Children’s Hospital, St. Louis, Missouri 63110
3. Program for Developmental and Reproductive Biology (H.P., S.K., M.H.), Children’s Hospital, Biomedicum Helsinki, University of Helsinki, 00290 Helsinki, Finland
4. Department of Physiology (J.L.), University of Oulu, 90220 Oulu, Finland
5. Department of Physiology (N.R.), Institute of Biomedicine, University of Turku, 20520 Turku, Finland