In this review, acute promyelocytic leukemia (APL), chronic myeloid leukemia (CML), and acute myeloid leukemia (AML) with RUNX1-RUNX1T1 were selected to consider minimal requirements for cancer initiation based on a simplified model. This evidence concerns the gene RUNX1T1 and chronic myelogenous leukemia, BCR-ABL1 positive.