1. From the Department of Medicine and Therapeutics and Li Ka Shing Institute of Health Sciences (X.R.H., A.C.K.C., H.Y.L.), Chinese University of Hong Kong, Hong Kong, China; Department of Medicine (F.Y., W.Y., C.P.L., H.F.T.), University of Hong Kong, Hong Kong, China; Mammalian Genetics Section (C.D.), National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Md.