In the present study, we also detected the t(7;21) unexpectedly as a result of our standard cytogenetic diagnosis of AML patients using interphase FISH analyses of bone marrow cells and searching for −5/del(5q), PML/RARα, del(17p), AML1/ETO, trisomy 8, −7/del(7q), CBFβ/MYH11 and del(20q). This evidence concerns the gene RUNX1 and acute myeloid leukemia.