The second major group of patients with well-established molecular targets for MRD monitoring are those with CBF AML defined by the presence of either the inv(16)(p13q22) CBFB-MYH11 or the t(8;21)(q22;q22) RUNX1-RUNX1T1 fusion. The gene discussed is CEBPZ; the disease is acute myeloid leukemia.