title: Lack of association between CYP17 MspA1 polymorphism and breast cancer risk: a meta-analysis of 22,090 cases and 28,498 controls.
abstract: Epidemiological studies have evaluated the association between CYP17 MspA1 polymorphism and breast cancer risk. However, the results remain conflicting rather than conclusive. To derive a more precise estimation of the relationship, we performed this meta-analysis. Systematic searches of the PubMed and Medline databases were performed. A total of 35 studies including 22,090 cases and 28,498 controls were identified. Genotype distributions of CYP17 in the controls of all studies were in agreement with Hardy-Weinberg equilibrium (HWE) except for three studies. When all 35 studies were pooled into the meta-analysis, there was no evidence for significant association between CYP17 MspA1 polymorphism and breast cancer risk (for A1/A2 vs. A1/A1: OR = 1.00, 95% CI = 0.96-1.04; for A2/A2 vs. A1/A1: OR = 1.03, 95% CI = 0.97-1.08; for dominant model: OR = 1.01, 95% CI = 0.97-1.05; for recessive model: OR = 1.03, 95% CI = 0.98-1.08). In the subgroup analyses by ethnicity, menopausal status and source of controls, no significant associations were found in all genetic models. When sensitivity analyses were performed by excluding HWE-violating studies, all the results were not materially altered. In summary, the meta-analysis strongly suggests that CYP17 MspA1 polymorphism is not associated with increased breast cancer risk.
authors.affiliation: Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Mao
authors.forename: Xi-Wen
authors.initials: XW
authors.lastname: Wang
authors.forename: Ben-Fu
authors.initials: BF
authors.lastname: He
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Qiu
authors.forename: Ru-Yan
authors.initials: RY
authors.lastname: Liao
authors.forename: Rong-Cheng
authors.initials: RC
authors.lastname: Luo
authors.forename: Qing
authors.initials: Q
authors.lastname: Chen
mesh_terms: D019943:Amino Acid Substitution; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000208:ethnology / Q000235:genetics; D016022:Case-Control Studies; D005006:Ethnicity / Q000235:genetics / Q000706:statistics & numerical data; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008593:Menopause; D008957:Models, Genetic; D016017:Odds Ratio; D018579:Patient Selection; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D012306:Risk; D013254:Steroid 17-alpha-Hydroxylase / Q000235:genetics*
chemical_list: C501892:CYP17A1 protein, human; D013254:Steroid 17-alpha-Hydroxylase