The most frequently mutated genes in MDS patients are involved in RNA splicing (SF3B1, SRSF2, U2AF1, ZRSR2) and in epigenetic regulation of DNA, including methylation (TET2, DNMT3A, IDH1/2) and chromatin regulation (ASXL1, EZH2) processes. This evidence concerns the gene ASXL1 and myelodysplastic syndrome.