In concordance with the expanded list of myelodysplasia-associated genes from the WHO and ICC, mutations in ASXL1, BCOR, EZH2, RUNX1, SF3B1, SRSF2, STAG2, U2AF1, or ZRSR2 are now considered adverse-risk based on updated prognostic studies in MDS, de novo AML, and secondary AML (sAML) [25–28, 39, 40]. This evidence concerns the gene U2AF1 and myelodysplastic syndrome.