ERCC2 and lip and oral cavity carcinoma: Two SNPs in XPD have been shown to be involved in susceptibility to oral cancer: codon 312 (G > A substitution at position 23,951, exon 10, Asp > Asn, rs1799793) and codon 751 (A > C substitution at nucleotide position 35,931, exon 23, Lys > Gln, rs13181) [9].