David P. Steensma

David P. Steensma is a physician-scientist and recognized thought leader on the biology and clinical management of myelodysplastic syndromes and the related phenomenon of clonal hematopoiesis of indeterminate potential (CHIP). Based at the Dana-Farber Cancer Institute and Harvard Medical School, his research has illuminated how acquired somatic mutations in hematopoietic stem cells accumulate with age, how they give rise to clonal advantage, and how specific mutation patterns (particularly in RNA splicing factors and epigenetic regulators) determine MDS phenotype, disease behavior, and treatment outcomes. Steensma was among the first to characterize the clinical significance of somatic mutations in the RNA splicing factor genes SF3B1, SRSF2, U2AF1, and ZRSR2 in MDS, demonstrating that SF3B1 mutations define a distinct, relatively favorable-risk subtype associated with ring sideroblast morphology and aberrant splicing of mitochondrial iron transport genes. He has been a major contributor to the evolving WHO and ICC classification of MDS, advocating for molecularly-defined entities that better predict prognosis and therapy response than morphology alone. His group has also published extensively on the functional consequences of splicing factor mutations in stem cell assays and mouse models, providing mechanistic insight into how these mutations drive ineffective erythropoiesis. A gifted medical writer, Steensma is widely read for his accessible and authoritative review articles on CHIP, clonal cytopenias of undetermined significance (CCUS), and the distinction between benign age-related clonal expansion and MDS. He has served on ASH, NCCN, and IWG MDS committees, contributes regularly to educational programs at ASH and EHA, and is a respected mentor for hematology fellows and junior faculty at Dana-Farber. His influence extends to the definition of new disease entities—including the 2022 ICC and WHO recognition of clonal cytopenia entities—that reshape how borderline cases between CHIP and MDS are categorized and managed.