Somatic mutations and chromosomal rearrangements involving Runx1 are frequently observed in abnormal hematopoietic cells in myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and chronic myelomonocytic leukemia (CMML) patients22. The gene discussed is RUNX1; the disease is chronic myelomonocytic leukemia.