DIAPH1 and Thrombocytopenia: In addition, the observation of a myeloproliferative- and a myelodysplastic-like phenotype in a different Diaph1 knock-out mouse [54] suggests that the DIAPH1 gene plays a critical negative regulatory role in myelopoiesis and is consistent with the thrombocytopenia observed in humans carrying DIAPH1 gain-of-function mutations.