TAL1 and acute lymphoblastic leukemia: TAL1 is overexpressed in approximately 60% of T‐ALL cases, and among these cases, about 30% are known to exhibit this phenotype due to a ~90 kb microdeletion that translocates the TAL1 gene with the promoter of the neighboring STIL gene.36 We found that the CIMP− subgroup was strongly associated with increased TAL1 gene expression, and a higher frequency of STIL‐TAL1 fusions was observed within this group.