ABL1 and acute lymphoblastic leukemia: In the Mexican pediatric ALL population, the sum of the frequencies of common molecular subtypes (BCR::ABL1, KMT2A::AFF1, ETV6::RUNX1, and TCF3::PBX1) has been variously reported to be 24.2% [35], 17.7% [36], and 18.83% [37].