Mutations in 11 genes were detected of which the most likely candidates for AML pathogenesis were: DNMT3A, BCOR, YY2 and SSRP1. The frequency of BCOR mutation was 17.1% in AML index patients, whereas the overall frequency of BCOR in unselected CN-AML was 3.8%. The gene discussed is BCOR; the disease is acute myeloid leukemia.