[Show abstract][Hide abstract] ABSTRACT: An abnormal immune response to common infection(s) may be a plausible etiological mechanism in childhood leukemia. We investigated whether 931 tagging single nucleotide polymorphisms (SNPs) selected in gene regions related to immune response are associated with childhood leukemia susceptibility in a hospital-based case-control study (63 cases and 148 controls) conducted among Korean children. The AT or TT genotype of rs7939734 in Fas-associated protein with death domain (FADD) was associated with increased risk of childhood leukemia compared with the AA genotype (odds ratio [OR] = 2.26, 95% confidence interval [95% CI] = 1.20-4.25, p(trend) = 0.0007, min p = 0.002, false discovery rate [FDR] p = 0.17). The CG or GG genotype of rs2301696 in TRPM5 was associated with decreased risk of childhood leukemia compared with the CC genotype (OR = 0.30, 95% CI = 0.14-0.63, p(trend) = 0.002, min p = 0.004, FDR p = 0.17). Our findings suggest that genetic polymorphisms in immune response genes might play a role in childhood leukemia development with limited biologic evidence.