XPC codon 939 polymorphism is associated with susceptibility to DNA damage induced by aflatoxin B1 exposure.

Aflatoxin B1 (AFB1), resulting in the formation of AFB1-DNA adducts, is a known human carcinogen. AFB1-exposure individuals with inherited susceptible carcinogen-repairing genotypes may experience an increased risk of genotoxicity. This study was aimed to investigate whether DNA repair gene xerodermapigmentosum complementation group C codon 939 polymorphism (rs2228001) affected the levels of AFB1-DNA adducts in Guangxi Population (n = 2558), from an AFB1-exposure area. AFB1-DNA adducts were measured by ELISA, and XPC codon 939 genotypes were identified by TaqMan-PCR. We found that longer AFB1-exposure years significantly increased XPC genotypes with codon 939 Gln alleles (namely, XPC-LG and -GG, odds ratios [95% confidence intervals] were 1.37 (1.15-1.63) and 1.99 (1.55-2.55), respectively) was significantly associated with higher levels of AFB1-DNA adducts. Furthermore, there was a positive joint effect between XPC genotypes and long-year AFB1 exposure in the formation of AFB1-DNA adducts. These results suggest that individuals with susceptible genotypes XPC-LG and -GG may experience an increased risk of DNA damage elicited by AFB1 exposure.