It has been revealed that aberrations of DNA repair proteins such as hOGG1, XRCC1, TP53, Poly(ADP-ribose) polymerase 1 (PARP-1), Mre11-Rad50-Nbs1 (MRN) complex, and ataxia telangiectasia-mutated (ATM) kinase were correlated with HCC [111–117]. The gene discussed is XRCC1; the disease is hepatocellular carcinoma.