XRCC1 and acute lymphoblastic leukemia: In studies of the DNA BER pathway, the OGG1 Ser326Cys polymorphism has been linked to the risk of pediatric ALL: the OGG1 Cys/Cys genotype increases ALL risk, while combined XRCC1/OGG1 or OGG1/MUTYH genotypes confer protection against this malignancy (44).