1. Departments of Medicine (M.A., C.G., X.L., S.R., R.E.W.), The University of Chicago, Chicago, Illinois 60637
2. Instituto de Biofisica Carlos Chaga Filho (T.O.-C.), Universidade Federal do Rio de Janeiro, Rio de Janeiro RJ 21941-941, Brasil
3. Departments of Metabolism Division (D.S.M., F.E.W.), Departments of Pediatrics and Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287
4. Departments of Pediatrics (S.R., R.E.W.), The University of Chicago, Chicago, Illinois 60637
5. Committees on Genetics (S.R., R.E.W.), The University of Chicago, Chicago, Illinois 60637
6. Departments of Molecular Medicine (S.R.), The University of Chicago, Chicago, Illinois 60637