U2AF1 and acute myeloid leukemia: The prevalence of complex karyotype was significantly lower in AML with alterations of ASXL1, EZH2, SRSF2, or STAG2. Significantly lower white blood cell counts at initial diagnosis were found for AML patients with alterations in ASXL1, BCOR, EZH2, SRSF2, STAG2, U2AF1, and RUNX1. Significantly lower peripheral and bone marrow blast counts were found for AML patients with mutations in ASXL1, SF3B1, SRSF2, STAG2, U2AF1, and RUNX1, while for BCOR- and EZH2-mutated AML, only peripheral blood blast counts were significantly lower.