Genetic Polymorphism rs6505162 in MicroRNA-423 May Not Be Associated with Susceptibility of Breast Cancer: A Systematic Review and Meta-Analysis

Background MicroRNA-423 (miR-423) rs6505162 polymorphism is found to be associated with breast cancer (BC) risk. However, the results were inconsistent. This study meta-analyzed the literature on possible association between rs6505162 polymorphism and BC risk.Methods PubMed, Embase, Google Scholar, and the Chinese National Knowledge Infrastructure (CNKI) databases were systematically searched to identify relevant studies. Meta-analyses were performed to examine the association between rs6505162 polymorphism and BC.Results None of the five genetic models suggested a significant association between rs6505162 polymorphism and BC risk: allelic model, OR 1.02, 95% CI 0.18–1.28, P =0.85; recessive model, OR 0.99, 95% CI 0.72–1.38, P =0.97; dominant model, OR 0.93, 95% CI 0.72–1.21, P =0.60; homozygous model, OR 1.04, 95% CI 0.66–1.65, P =0.87; and heterozygous model, OR 1.07, 95% CI 0.90–1.28, P =0.45. Similar results were obtained in subgroup analyses of Asian, Chinese, and Caucasian patients.Conclusion The available evidence suggests no significant association between rs6505162 polymorphism and BC risk. These conclusions should be verified in large, well-designed studies.