It was suggested by the researchers that the association of the PACSIN2 genotype with 6-MP-related toxicity occurs through the modulation of TPMT activity, a hypothesis that was confirmed in in vitro cell models as well as in ALL patients, where individuals with the PACSIN2 rs2413739 CC genotype had higher TPMT activity than patients with the TT genotype12. This evidence concerns the gene TPMT and acute lymphoblastic leukemia.