Association of COL5A1 gene polymorphisms and risk of tendon-ligament injuries among Caucasians: a meta-analysis

BACKGROUND: Tendons and ligaments are common sites of musculoskeletal injuries especially during physical activity. The multifactorial etiology of tendon-ligament injury (TLI) includes both genetic and environmental factors. The genetic component could render influence on TLI risk to be either elevation or reduction. OBJECTIVE: Inconsistency of reported associations of the collagen type V alpha 1 chain (COL5A1) polymorphisms, mainly rs12722 (BstUI) and rs13946 (DpnII), with TLI warrant a meta-analysis to determine more precise pooled associations. METHODS: Multi-database literature search yielded eight articles (11 studies) for inclusion. Pooled odds ratios (ORs) and 95% confidence intervals were used to estimate associations. Heterogeneity of outcomes warranted examining their sources with outlier treatment. RESULTS: All rs12722 effects indicated reduced risk (OR < 1.0). The significant outcomes (ORs 0.59–0.77, p = 0.0009–0.04) in the pre-outlier analysis were non-heterogeneous (p > 0.10). The non-significant and heterogeneous (ORs 0.63–0.98, p = 0.13–0.95; up to I(2) = 86%) pre-outlier rs12722 and rs13946 results became significant (ORs 0.32–0.78, p = 10(−5)−0.01) and heterogeneity eliminated (I(2) = 0%) with outlier treatment. Significant associations (ORs 0.26–0.65, p = 0.002–0.03) were also observed in other COL5A1 polymorphisms (rs71746744 and rs16399). Sensitivity analysis deemed all significant outcomes to be robust. CONCLUSIONS: In summary, COL5A1 polymorphisms reduce the risk of TLI among Caucasians. These findings are based on the evidence of significance, homogeneity, consistency, and robustness. Additional studies are warranted to draw more comprehensive conclusions. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s40798-018-0161-0) contains supplementary material, which is available to authorized users.