Omar Abdel-Wahab is an Assistant Member in the Human Oncology and Pathogenesis Program (HOPP) and an Attending Physician on the Leukemia Service in the Department of Medicine at Memorial Sloan-Kettering Cancer Center. Dr. Abdel-Wahab’s research focuses on the role of disordered epigenetic modifiers in the pathogenesis of hematopoietic malignancies. As a postdoctoral fellow in Ross Levine’s lab (also part of HOPP), Dr. Abdel-Wahab was instrumental in identifying the clinical, prognostic, and biological significance of mutations in a number of epigenetic modifiers newly identified in patients with acute myeloid leukemia, myelodysplastic syndrome, and myeloproliferative neoplasms. For instance, he identified that mutations in the gene ASXL1 are loss-of-function mutations that are correlated with genome-wide abundance of the transcriptionally repressive histone H3 lysine 27 methylation. This discovery then led to the identification of ASXL1 as a critical mediator of Polycomb-mediated repression in hematopoietic cells. Further creation of a novel conditional knockout model of ASXL1 in mice revealed a number of important functions of ASXL1 in development and hematopoiesis. Current areas of investigation include: