By sequencing of 42 genes which are related with acute myeloid leukemia/myeloproliferative neoplasms/myelodysplastic syndrome including ASXL1, CALR, CBL, CEBPA, CSF3R, CUX1, DNMT3A, EED, ETV6, EZH2, FLT3, GATA2, GNAS, HRAS, IDH1, IDH2, IKZF1, JAK2, JAK3, KDM6A, KIT, KRAS, MPL, NF1, NOTCH1, NPM1, NRAS, PTPN11, RUNX1, SETBP1, SF3B1, SH2B3, SRSF2, STAG2, SUZ12, TET2, TP53, U2AF1, WT1, BCOR, PHF6, and ZRSR2, the mutations of c-Kit (p.D816V, 32.35%), DNMT3A (p.R882H, 45.15%) were detected (Fig. 4). The gene discussed is DNMT3A; the disease is myelodysplastic syndrome.