A1166C polymorphism of the angiotensin II type 1 receptor gene contributes to hypertension susceptibility: evidence from a meta-analysis.

Background The angiotensin II type 1 receptor (AT1R) gene is a prime candidate for polymorphisms that could contribute to hypertension. A polymorphism in the 3' untranslated region, leading to the transversion of adenine to cytosine at position 1166, has been the most-studied variant. However, the results have been inconsistent, and we therefore performed a meta-analysis to evaluate the association of this polymorphism with hypertension. Methods We conducted an extended a computer-based literature search of PubMed and Web of Knowledge up to November 30, 2015. The extracted data were analysed statistically, and pooled odds ratios with 95% confidence intervals were calculated to assess the strengths of associations using Review Manager software (version 5.2). Results After removing 5 studies that were not consistent with the Hardy-Weinberg equilibrium, we finally collected 41 case-control studies involving 11,837 cases and 11,020 controls to evaluate the association between AT1R polymorphisms and hypertension. We found that the risk of hypertension was higher for allele C than for allele A under the codominant model, significantly higher for genotype CC + AC than for genotype AA under the dominant model, and significantly higher for genotype CC + AC in Caucasians. Conclusion This meta-analysis suggests that the AT1R 1166 CC + AC genotype consistently confers susceptibility to hypertension and that early preventive measures should be applied in clinical settings according to patient genotypes.