A systematic review of vitamin D receptor gene polymorphisms and prostate cancer risk

Purpose: Polymorphisms in the vitamin D receptor gene have been hypothesized to alter the risk of prostate cancer. However, studies investigating the associations between specific vitamin D receptor polymorphisms and prostate cancer risk have yielded inconsistent results. Materials and Methods: We performed a meta-analysis of 26 studies evaluating the association between vitamin D receptor TaqI, poly(A), BsmI, ApaI, and/or FokI polymorphisms, and prostate cancer risk. Results: The studies were heterogeneous in terms of study design, selection of cases and controls, and racial composition. Random effects models were used to estimate the pooled OR and 95% CI of each vitamin D receptor polymorphism under codominant, additive, dominant and recessive genetic models. Overall we did not find evidence to support an association between any of the vitamin D receptor polymorphisms and the risk of prostate cancer. For TaqI, which is the most studied vitamin D receptor polymorphism with 18 studies (total of 2,727 cases and 3,685 controls), the pooled OR was 1.00 (95% CI 0.85 to 1.18) for the Tt vs TT genotypes, 0.94 (95% CI 0.78 to 1.13) for the tt vs TT genotypes and 0.89 (95% CI 0.71 to 1.10) for the recessive model (tt vs Tt plus TT). ORs for the poly(A) microsatellite, BsmI, ApaI and FokI polymorphisms were similar. Conclusions: The results of this meta-analysis suggest that the vitamin D receptor TaqI, poly(A), BsmI, ApaI and FokI polymorphisms are not related to prostate cancer risk.