The following fusion partner genes were found in t-ALL cases: ACTN4, AFDN, AFF1 (n = 20), CEP164, CREBBP, EPS15, FOXO3 (n = 2), MAML2 (n = 3), MLLT1, MLLT10, PRCC1, 21q22; in t-AML the following fusion partners were diagnosed: ACTN4, AFDN (n = 3), AKAP13, ARHGEF12 (n = 2), CBL, CEP170B (n = 2), CREBBP, ELL (n = 13), EPS15, GMPS, KNL1, LAMC3, ME2, MLLT1 (n = 9), MLLT10 (n = 3), MLLT3 (n = 47), PDS5A, KMT2A-PTD (n = 5), SEPTIN11, SEPTIN9 (n = 2), SNX9, TCF12, TET1 and (inv)11p12. This evidence concerns the gene AFF1 and acute myeloid leukemia.