Lack of association between vitamin D receptor polymorphisms ApaI (rs7975232) and BsmI (rs1544410) and osteoporosis among the Han Chinese population: A meta-analysis

In this study, we aimed to assess the relationship between vitamin D receptor gene polymorphisms and osteoporosis in the Han Chinese population. Articles regarding associations between vitamin D receptor polymorphisms (ApaI rs7975232 and BsmI rs1544410) and osteoporosis were retrieved from databases in November 2014. Eligible studies were tested by the Hardy-Weinberg equilibrium. The odds ratio and 95% confidence interval (95% CI) were analyzed to evaluate the strength of the associations. Pooled effect estimates were derived using a fixed-effect model and a random-effect model according to the heterogeneity of the test results. A subgroup analysis by study type and a sensitivity analysis based on studies that conform to the Hardy-Weinberg equilibrium and studies with postmenopausal women as participants were performed. This meta-analysis involved 15 eligible studies including 1580 cases and 1389 controls. The pooled estimated odds ratios in the dominant and additive genetic models were 0.73 (95% CI: 0.46-1.14, p = 0.17) and 1.01 (95% CI: 0.77-1.33, p = 0.81), respectively, for rs7975232 and 1.01 (95% CI: 0.81-1.26, p = 0.91) and 1.01 (95% CI: 0.77-1.33, p = 0.92), respectively, for rs1544410. The subgroup analysis showed that regardless of the dominant or additive genetic model, the effect of pooled odds ratios for rs7975232 and rs1544410 was insignificant. The sensitivity analysis also showed that the pooled effect was not significantly changed. In conclusion, no evidence of association is apparent between polymorphisms of vitamin D receptor genes and osteoporosis risk in the Han Chinese population.