In contrast to inv(16) AML, t(8;21) AML presents with a high frequency of mutations in genes regulating chromatin conformation (epigenetic modifiers) such as ASXL1 and ASXL2 or encoding members of the cohesin complex such as RAD21 and SMC1A [41,42]. The gene discussed is RAD21; the disease is acute myeloid leukemia.