title: Cytochrome P450 2A6 deletion polymorphism and risk of lung cancer: a meta-analysis.
abstract: Previous studies concerning the association between cytochrome P450 2A6 (CYP2A6) deletion polymorphism and lung cancer risk provided controversial results. To clarify the precise association, a meta-analysis was performed. The electronic databases PubMed, Chinese Biomedical Database and Chinese National Knowledge Infrastructure Database were searched for case-control studies last updated on June 3, 2012 that investigated CYP2A6 deletion polymorphism and lung cancer risk. The odds ratio (OR) and its respective 95 % confidence interval (95 % CI) were used to measure the strength of association by means of a genetic model free approach. A total of 8 studies including 2,607 cases and 2,595 controls met the inclusion criteria and were subjected to the final analysis. The most appropriate co-dominant model was adopted. Overall, we found that CYP2A6 *1/*1 genotype was associated with an increased risk of lung cancer relative to *4/*4 genotype (OR = 2.65, 95 % CI: 1.84-3.81, P < 0.001). Significant association was also detected among Asians. Publication bias was absent in this meta-analysis. Therefore, our data suggested that the presence of the CYP2A6 *1/*1 might be associated with an increased lung cancer risk, especially for Asians. Further studies well-designed among different ethnicity populations are required.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Medicine and Geriatrics, The Fourth Affiliated Hospital of Anhui Medical University, Hefei, 230022, Anhui, China.
authors.forename: Zheng-Bing
authors.initials: ZB
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Shu
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Wang
authors.forename: Cheng
authors.initials: C
authors.lastname: Jin
authors.forename: Zhi-Xia
authors.initials: ZX
authors.lastname: Lou
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics*; D044466:Asian People / Q000235:genetics; D002872:Chromosome Deletion; D019295:Computational Biology; D065637:Cytochrome P-450 CYP2A6; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics*; D008957:Models, Genetic; D016017:Odds Ratio; D011110:Polymorphism, Genetic
chemical_list: D001189:Aryl Hydrocarbon Hydroxylases; C585710:CYP2A6 protein, human; D065637:Cytochrome P-450 CYP2A6