Given the high incidence of AML in Mexican children, as well as the importance of knowing the epidemiological behavior of AML1-ETO, PML-RARA, CBFB-MYH11, MLL-AF9, and BCR-ABL1p210 for diagnosis and best treatment selection, the aims of this multicenter study performed by the Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia (MIGICCL) were to determine the frequencies of these five common fusion genes in children with AML from Mexico City. The gene discussed is RUNX1; the disease is childhood leukemia.