1. Diabetes Research Center, Qatar Biomedical Research Institute; Hamad Bin Khalifa University, Qatar Foundation, Education City; Doha Qatar
2. Larry L. Hillblom Islet Research Center, David Geffen School of Medicine; University of California; Los Angeles CA 90095 U.S.A.
3. Department of Medicine; Weill Cornell Medicine in Qatar, Qatar Foundation, Education City, PO BOX 24144; Doha Qatar
4. Department of Medicine; Qatar Metabolic Institute, Hamad Medical Corporation; Doha Qatar