The association between XPG Asp1104His polymorphism and colorectal cancer risk in the Chinese population

Abstract

Objective Some studies have reported that the Asp1104His polymorphism in Xeroderma Pigmentosum complementation group G (XPG) was significantly associated with the colorectal cancer (CRC) susceptibility, although the previous results were inconsistent. This study was aiming to investigate whether there existed an association between XPG Asp1104His polymorphism and CRC risk in an independent Chinese population. Methods A total of 878 CRC cases and 884 healthy controls were recruited in our analysis. We used the TaqMan assay to genotype XPG Asp1104His and evaluated its association with CRC susceptibility. A further meta-analysis was performed to consolidate the results. Results We found that XPG Asp1104His polymorphism was associated with a significantly increased CRC risk (dominant model: His/His+ Asp/His vs. Asp/Asp, adjusted OR=1.39, 95%CI=1.14~1.69). Stratification analysis by clinical characteristics indicated that the His/His+ Asp/His genotypes were associated with increased CRC susceptibility in patients with moderately differentiated grade (OR=1.44, 95%CI=1.17~1.78), but not in poorly and well differentiated grade. Furthermore, we identified that the meta-analysis reported a similar results in dominant model (OR=1.35; 95%CI=1.20~1.51). Especially, when stratified by ethnicity, an evidently increased risk was identified in the Asian population. Conclusions Our findings suggested that XPG Asp1104His polymorphism could increase the susceptibility of CRC in Asian populations. Key words: Colorectal neoplasms; Disease susceptibility; Polymorphism, single nucleotide; XPG