RUNX1 and leukemia: Now known as core binding factor (CBF) leukemias, those with t(8;21)(q22;q22) with resulting RUNX1-RUNX1T1 fusion (formerly AML1-ETO) and inv(16)(p13q22)/t(16;16)(p13;q22) with resulting CBFB-MYH11 fusion gene carry favorable prognoses.