Vitamin D receptor gene ApaI polymorphism and breast cancer susceptibility: a meta-analysis

Vitamin D receptor (VDR) principally mediates the anticancer activities of vitamin D. Many studies investigated the association between VDR gene ApaI polymorphism and breast cancer, but the results were inconclusive. We performed this meta-analysis to evaluate the association between VDR gene ApaI polymorphism and breast cancer. Twelve studies with a total of 8,254 subjects were identified from PubMed and Wanfang databases. The pooled odds ratio (OR) and confidence intervals (95 % CI) were used to assess the association. The meta-analysis indicated that VDR gene ApaI polymorphism was not associated with risk of breast cancer (a vs. A: OR?=?0.97, 95 % CI 0.91–1.04, P?=?0.378; aa vs. AA: OR?=?0.97, 95 % CI 0.85–1.10, P?=?0.618; aa vs. AA + Aa: OR?=?1.00, 95 % CI 0.89–1.12, P?=?0.972; aa + Aa vs. AA: OR?=?0.95, 95 % CI 0.82–1.11, P?=?0.550). Subgroup analysis by ethnicity further showed that VDR gene ApaI polymorphism was not associated with risk of breast cancer in both Asians and Caucasians. These data from the meta-analysis indicate that VDR gene ApaI polymorphism is not associated with breast cancer susceptibility.