Genetic effects of rs3740199 polymorphism in ADAM12 gene on knee osteoarthritis: a meta-analysis

Background: Knee osteoarthritis (OA) is a complex arthritic condition in which genetic factors play an important role. ADAM12 gene is one of the recognized candidate genes although the results are conflicting. To derive a more precise estimation of the association between rs3740199 polymorphism in ADAM12 gene and risk of knee OA, we performed a meta-analysis based on six related studies, including a total of 2185 cases and 3716 controls. Methods: A comprehensive search was performed to identify related studies up to April 14, 2017. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association. Different genetic models were used to assess the pooled and stratified data. Results: Overall, no significant association was found in all genetic models (C vs. G, OR = 0.983, 95% CI = 0.910-1. 061; CC vs. GG, OR = 1.033, 95% CI = 0.851-1.255; CG vs. GG, OR = 1.030, 95% CI = 0.877-1.209; CC/CG vs. GG, OR = 1. 031, 95% CI = 0.886-1.201; CC vs. CG/GG, OR = 1.017, 95% CI = 0.868-1.190). When stratified by ethnicity, no significant association was found. Conclusions: This meta-analysis suggested that the rs3740199 polymorphism does not contribute to the development of knee OA. Additional well-designed large studies are required to confirm these findings in different populations.