Aaron Leong MD, MSc

Dr. Aaron Leong is an endocrinologist at Massachusetts General Hospital, Assistant Professor of Medicine at Harvard Medical School, and Associate Member of the Broad Institute. He serves as Associate Director of the Boston Area Diabetes Endocrinology Research Center (BADERC) and directs its Pilot and Feasibility Program and BADERC-Broad Program. His research translates human genetic discoveries into better diabetes screening, diagnosis, and treatment. Using ancestrally diverse biobanks linked to electronic health records and recall-by-genotype studies, his team investigates how inherited variation shapes type 1 and type 2 diabetes risk, underlying physiology, and treatment response. A longstanding focus of his work is hemoglobin A1c: he has shown that genetic differences affecting red blood cells can alter A1c independently of blood glucose, potentially changing how diabetes is diagnosed and risk is assessed across diverse populations. His studies pair large-scale genetic analyses with metabolic testing and pharmacologic interventions in humans. Current projects include the NIH-funded R01 Recall by Genotype in Diabetes Risk Spectrum and the PATHS studies of genetics-guided type 1 diabetes screening and biological heterogeneity in type 2 diabetes. He is also Principal Investigator of the MGH site for the Epidemiology of Diabetes Interventions and Complications (EDIC) study, the long-term follow-up of the landmark Diabetes Control and Complications Trial.