The AA, AG, and GG genotype frequencies of RAD18 rs250403 were 60.9%, 33.1%, and 6.0% in the controls; 54.6%, 32.9%, and 12.5% in the CIN III group and 45.2%, 32.2%, and 22.6% in the CSCC group, respectively. This evidence concerns the gene RAD18 and skin squamous cell carcinoma.