Three well-known fusions in AML were identified in four abnormal karyotype AML cases, including RUNX1-RUNX1T1 fusion in two cases [46,XXt(8;21)(q22;q22); 46,XYt(8;21)(q22;q22)], MLL-MLLT1 fusion in one case [48,XX,+8,+8,i(8)(q10)/49,idem,+i(8)(q10)] and MLL-MLLT3 fusion in one case [46,XY,t(9;11;11)(p22;q23;p11.2)]. The gene discussed is RUNX1; the disease is acute myeloid leukemia.