RUNX1-RUNX1T1+ leukemia is one of the most common cytogenetic subtypes of AML, and the RUNX1-RUNX1T1 fusion protein plays an important triggering role in the pathogenesis of t(8;21) AML by regulating gene expression through various mechanisms1,19,20. The gene discussed is RUNX1T1; the disease is acute myeloid leukemia.