Additionally, the riskallele of AFF1 rs340630 polymorphism was found to be associatedwith the increase in transcript levels of AFF1, indicating thispolymorphism is functional (11).AFF1 was first identified as a fusion partner withmyeloid/lymphoid, or mixed-lineage leukemia (MLL) in an acute lymphoblastic leukemia(ALL) patient (22), being predominantlyexpressed in a lymphocyte system (23,24). This evidence concerns the gene KMT2A and acute lymphoblastic leukemia.