부산대학교 도서관

The VDR gene is an important regulator of the vitamin D pathway, and the role of some of its polymorphisms on cancer risk was previously investigated. A trend of cancer risk reduction with the VDR BsmI B allele was observed for many cancer sites. We performed a comprehensive meta-analysis to investigate the role of VDR BsmI polymorphism on cancer risk, even according to different ethnicities. Summary odds ratios (SORs) were calculated with random-effects models and maximum likelihood estimation. We categorized studies into three groups (“moderate”, “high” and “very high confidence”) according to departure from Hardy–Weinberg equilibrium in controls, reported minor allele frequency and genotyping quality controls. The meta-analysis included 73 studies with 45,218 cases and 52,057 controls. We found a significant 6–7% reduction of cancer risk at any site respectively for carriers of Bb genotype (SOR; 95%CI: 0.94; 0.90–0.99) and for carriers of BsmI BB genotype (SOR; 95%CI: 0.93; 0.89–0.98) compared to bb carriers, and they remain statistically significant when we restricted the analysis to at least “high confidence” studies. For skin cancer, a significant risk reduction was observed for Bb carriers (SOR; 95%CI: 0.86; 0.76–0.98). We also found a significant reduction of colorectal cancer risk for BB and Bb + BB genotypes carriers, but these SORs were no more significant when we restricted the analysis to studies with “high confidence”. When the analysis was stratified by ethnicity, we still observed a significant decreased risk for both Bb and BB compared to bb genotype among Caucasians: SORs (95%CI) for any cancer site were 0.97 (0.93–1.00) and 0.95 (0.91–0.99), respectively. Among other ethnic groups the inverse association was still present, but did not reach statistical significance. In conclusion, we suggest a weak effect of BsmI B allele in reducing cancer risk at any site, especially of the skin. [ABSTRACT FROM AUTHOR]