Following the decitabine administration, it was shown that the VAF of SETD2 p.(P1962L) (Sample 55, 21% vs. 38%; Sample 46, 100% vs. 39%; Sample 69, 53% vs. 39%; Sample 37, 60% vs. 45%) and p.(N1155K) (Sample 42, 18% vs. 0%; Sample 44, 100% vs. 0%; Sample 84, 51% vs. 32%; Sample 46, 100% vs. 48%) experienced a marked change, which suggested the likely association with therapy outcome in MDS. The gene discussed is SETD2; the disease is myelodysplastic syndrome.