SF3B1 and SRSF2 mutations are mutually exclusive with U2AF1 in patients with myeloid neoplasms [44], and SF3B1, SRSF2, and TP53 mutations are shown to be inversely associated with U2AF1 in MDS patients [27,28,35,38,39]. The gene discussed is SF3B1; the disease is myelodysplastic syndrome.