Dr. Sweetser graduated with Honors from Stanford University, then completed his MD/PhD at Washington University School of Medicine in St. Louis, and Pediatric Residency training at St. Louis Children's Hospital. He completed his Medical Genetics Fellowship training at the Washington University School of Medicine in St. Louis and the University of Washington in Seattle along with a Biochemical Genetics Fellowship. He subsequently completed a Fellowship in Pediatric Hematology/Oncology at the University of Washington in Seattle. He is Board Certified in Clinical Genetics and Genomics, Clinical Biochemical Genetics, as well as Pediatric Hematology-Oncology.
Since 2003 Dr. Sweetser has been at MGH and sees patients in Medical Genetics and Metabolism and Pediatric Hematology/Oncology. He specializes in children and adults with metabolic disease, neurodevelopment disorders, complex undiagnosed disorders as well as those with inherited hematological disorders and children with genetic disorders predisposing to malignancies. He has been Chief of Medical Genetics and Metabolism at MGH since 2011 and was awarded the Lewis and Leslie Holmes Endowed Chair in Genetics and Teratology in 2017. He is Co-Director of the Pitt Hopkins Clinic, MGH Site Director of the Harvard Medical School Genetics Training program, Co-Director of the Harvard Medical School Affiliated Hospitals NORD Rare Disease Center of Excellence and a Primary Investigator in the MGH Center for Cancer Research. Dr. Sweetser is also the MGH site director for the NIH sponsored Undiagnosed Diseases Network linking 11 medical centers around the country to accelerate discovery and innovation in the way we diagnose and treat patients with previously undiagnosed diseases. He has been a leader in the application of genomic sequencing to clinical diagnostics and expanding clinical genomic applications throughout MGH. He has contributed to the discovery of numerous new genetic diseases.
Dr. Sweetser runs a research lab in the Center for Genomic Medicine and MGH Cancer Center investigating several genetic disorders including Pitt Hopkins Syndrome, IQSEC2 -related disorder, CACNA1E epileptic encephalopathy, as well as leukemia. He has systematically generated and characterized patient derived induced pluripotent stem cell (iPSC) models of several inherited monogenic causes of intellectual disability and neurodevelopmental disorders developing phenotypic assays amenable to drug screening to precision targeted therapeutics.