The association between XPD Asp312Asn polymorphism and lung cancer risk: a meta-analysis including 16,949 subjects

To derive a more precise estimation of the relationship between the xeroderma pigmentosum group D (XPD) Asp312Asn polymorphism and lung cancer risk, a meta-analysis was performed. PubMed, Medline, Embase, and Web of Science were searched. Crude ORs with 95% CIs were used to assess the strength of association between the XPD Asp312Asn polymorphism and lung cancer risk. The pooled ORs were performed with co-dominant model (Asp/Asn vs. Asp/Asp, Asn/Asn vs. Asp/Asp), dominant model (Asp/Asn + Asn/Asn vs. Asp/Asp), and recessive model (Asn/Asn vs. Asp/Asp+Asp/Asn), respectively. A total of 18 studies including 7,552 cases and 9,397 controls were involved in this meta-analysis. Overall, significantly elevated lung cancer risk was associated with XPD Asn allele when all studies were pooled into the meta-analysis (Asn/Asn vs. Asp/Asp: OR=1.158, 95% CI=1.018-1.317; recessive model: OR=1.161, 95% CI=1.029-1.311). In the subgroup analysis by ethnicity, significantly increased risks were found for both Caucasians (Asn/Asn vs. Asp/Asp: OR=1.164, 95% CI=1.003-1.351; recessive model: OR=1.169, 95% CI=1.016-1.345) and Asians (Asn/Asn vs. Asp/Asp: OR=8.056, 95% CI=2.420-26.817; recessive model: OR=7.956, 95% CI=2.391-26.477). When stratified by study design, statistically significantly elevated risk was noted in hospital-based studies (Asn/Asn vs. Asp/Asp: OR=1.315, 95% CI=1.110-1.558; recessive model: OR=1.290, 95% CI=1.099-1.513). In conclusion, this meta-analysis suggests that the XPD Asn allele is a low-penetrant risk factor for developing lung cancer.