BH3 profiling studies revealed that the dependency on BCL-2 or BCL-XL in T-ALL correlates with the maturation stage of the malignancy: while most T-ALL cases are BCL-XL-dependent, ETP-ALL exhibits preferential BCL-2 dependence and selective sensitivity to venetoclax (ABT-199) [109]. The gene discussed is BCL2L1; the disease is acute lymphoblastic leukemia.