As in myelodysplastic syndrome (MDS) and MDS-related diseases (such as chronic myelomonocytic leukemia and acute myloid leukemia) in which mutations in other genes of the spliceosome complex such as SRSF2 and U2AF1 are described [6,7,8,9,10], mutations in SRSF2 and other spliceosome factors are also observed in UM [11]. Here, U2AF1 is linked to myelodysplastic syndrome.