MTRR and acute lymphoblastic leukemia: Remarkably, the combination of rs1004474 (AA) - rs1532268 (GG) (i.e. the common homozygous case for both SNPs) had the highest conditional probability of risk of HD-ALL, namely 0.23, which exceeded the individual effect of risk allele A for MTRR rs1532268 with a conditional probability of risk of 0.14.