Association between polymorphisms in MicroRNA target sites of RAD51D genes and risk of hepatocellular carcinoma

RAD51D (RAD51L3) is a member of the RAD51 gene family which plays important roles in maintaining genomic stability and preventing DNA damage. This study is aimed to investigate the associations between RAD51D polymorphisms and the hereditary susceptibility of hepatocellular carcinoma (HCC). In this study we conducted a hospital-based case-control study including 805 cases (HCC patients) and 846 controls (nontumor patients) in Guangxi, China. A total of two Single-nucleotide polymorphisms (SNPs) rs12947947 and rs28363292 of RAD51D were selected and genotyped. Although we did not find two SNPs individually that had any significant main effect on risk of HCC, We found that the combined genotypes with 1-2 risk genotypes were associated with significantly increased overall risk of HCC (OR = 1.462, 95% CI = 1.050-2.036). According to the results of further stratification analysis, GT/GG genotype of rs28363292 increased HCC risk in zhuang people (OR = 3.913, 95% CI = 1.873-8.175) and nonhepatitis B virus (HBV) infection population (OR = 1.774, 95% CI = 1.060-2.969), the combined 1-2 risk genotypes increased the risk of HCC in zhuang people (OR = 2.817, 95% CI = 1.532-5.182) and non-HBV infected population (OR = 1.567, 95% CI = 1.042-2.358). Our results suggest that rs12947947 and rs28363292 polymorphisms may jointly contribute to the risk of HCC. Further large studies and functional studies are required to validate our findings.