RUNX1 and blood platelet disease: Familial platelet disorder with associated myeloid malignancies (FPDMM), also known as RUNX1-Familial Platelet Disorder (RUNX1-FPD, or FPD), is an autosomal dominant condition caused by deleterious RUNX1 variants and characterized by quantitative and qualitative platelet defects as well as a 35–45% lifetime risk of hematopoietic malignancies [1, 2].