Selected Polymorphisms of Base Excision Repair Genes and Pancreatic Cancer Risk in Japanese

Background: Although several reports have described a possible association between DNA repair genes and pancreatic cancer (PC) in smokers, this association has not been fully evaluated in an Asian population. We assessed the impact of genetic polymorphisms in the base excision repair (BER) pathway on PC risk among Japanese. Methods: This case-control study compared the frequency of 5 single-nucleotide polymorphisms (SNPs) of BER genes, namely rs1052133 in OGG1, rs1799782 and rs25487 in XRCC1, rs1130409 in APE1, and rs1136410 in PARP1. SNPs were investigated using the TaqMan assay in 185 PC cases and 1465 controls. Associations of PC risk with genetic polymorphisms and gene-environment interaction were examined with an unconditional logistic regression model. Exposure to risk factors was assessed from the results of a self-administered questionnaire. We also performed haplotype-based analysis. Results: We observed that the minor allele of rs25487 in XRCC1 was significantly associated with PC risk in the per-allele model (odds ratio = 1.29, Cl = 1.01-1.65; trend P = 0.043). Haplotype analysis of XRCC1 also showed a statistically significant association with PC risk. No statistically significant interaction between XRCC1 polymorphisms and smoking status was seen. Conclusions: Our findings suggest that XRCC1 polymorphisms affect PC risk in Japanese.