ERCC2 and gastric cancer: Those 15 studies were preliminarily appropriate to the meta-analysis of the associations with gastric cancer regarding XPD SNPs, among which 13 studies concerned XPD Lys751Gln polymorphism [16]–[26], [28], [29], 9 studies concerned XPD Asp312Asn polymorphism [17]–[21], [23], [27], [28], [30], and only 1 study concerned XPD Arg156Arg polymorphism [28].