According to the latest evidence [30] formulated on the theory of multistep outset of AML [3,44], CBF AML seems to result from the acquisition of a sequential order of mutations, affecting firstly transcription and differentiation (such as CBF) genes, followed by activating alterations that increase proliferation, such as class III RTKs. The gene discussed is CEBPZ; the disease is acute myeloid leukemia.