1. Division of Endocrinology (R.R.S., L.G.G., N.H., W.L.M.), Department of Pediatrics, University of California, San Francisco, San Francisco, California 94143
2. Endocrinology Service and Research Center (R.R.S., G.V.V.), Sainte-Justine Hospital, and Department of Pediatrics, University of Montreal, Montreal, Canada H3T 1C5