U2AF1 and myelodysplastic syndrome: Interestingly, comparing de novo and stringently defined secondary AMLs occurring after a documented phase of MDS, the French group identified a molecular subgroup, termed ‘secondary-type AML’, defined by mutations in either SRSF2, SF3B1, U2AF1, ZRSR2, ASXL1, EZH2, BCOR, and/or STAG2 genes.