U2AF1 and myelofibrosis: Laque Paz et al., as in other studies, observed that the most frequently mutated genes in myelofibrosis were ASXL1, TET2, SRSF2, U2AF1, and EZH2. In addition, they made very interesting observations dividing patients into four groups, namely, TP53-mutated patients, patients with ≥1 mutation in EZH2; CBL, U2AF1, SRSF2, IDH1, IDH2, NRAS, or KRAS - high-risk groups; ASXL1-only mutation; and “other” patients mainly mutated in the NFE2, DNMT3A, TET2, and SF3B1 genes.