Associations of Angiotensin‐Converting Enzyme Insertion/Deletion, Angiotensin II Receptor A1166C, and Endothelial Nitric Oxide Synthase 4b/a Gene Polymorphisms With Pregnancy Hypertensive Disorders: A Meta‐Analysis

There have been numerous studies concerning the associations of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D), angiotensin II receptor 1 (AT1R) gene A1166C, and endothelial nitric oxide synthase (eNOS) gene 4b/a polymorphisms with risk of pregnancy hypertensive disorders (PHDs). However, the results are inconsistent. A total of 83 eligible studies (10,354/18,446 cases/controls) were included in this meta-analysis. Pooled odds ratios with corresponding 95% confidence intervals were used to calculate these associations. The effects of ethnicity and types of PHDs were also considered. Results showed significant associations between the ACE gene polymorphism and PHDs in all of the populations except that in Africa. The associations also existed in AT1R, eNOS gene polymorphism and PHDs in part of the gene models in the overall population. These results indicated the ACE gene polymorphism was associated with an increased risk of PHDs, whereas the eNOS and AT1R gene polymorphism only have increased susceptibility to PHDs in part of the gene models.