Somatic and germline mutations in MDS patients affect genes encoding DNA methylation regulators (TET2 and DNMT3A), chromatin modifiers (ASXL1 and EZH2), splicing factors (SRSF2, U2AF1, and SF3B1), TFs (EVI1, RUNX1, and GATA2), and signaling pathway intermediates (3). The gene discussed is RUNX1; the disease is myelodysplastic syndrome.