Associations of ACE I/D, AGT M235T gene polymorphisms with pregnancy induced hypertension in Chinese population: a meta-analysis

Purpose There have been many studies concerning the associations of angiotensin-converting enzyme (ACE) I/D , angiotensinogen (AGT) M235T polymorphisms with pregnancy induced hypertension (PIH) among Chinese populations. However, the results were inconsistent, prompting the necessity of meta-analysis. Methods Studies published in English and Chinese were mainly searched in EMbase, PubMed and CBM up to January 2012. Results Twenty-three studies with 3,551 subjects for ACE I/D and seven studies with 1,296 subjects for AGT M235T were included. Significant associations were found between ACE I/D and PIH under dominant, recessive and allelic models. A separate analysis confined to preeclampsia suggested that ACE I/D was associated with preeclampsia under recessive model and allelic model, but not dominant model. Stratified analyses were conducted as meta-regression analysis indicated that the sample size of case group was a significant source of heterogeneity, which suggested no significant association between ACE I/D and PIH in the subgroup of more than 100 cases. Associations were found between AGT M235T and PIH under dominant genetic model (OR = 1.59; 95 %CI: 1.04–2.42), recessive genetic model (OR = 1.60; 95 %CI: 1.07–2.40), and allelic model (OR = 1.40; 95 %CI: 1.17–1.68). No publication bias was found in either meta-analysis. Conclusions The present meta-analysis suggested significant associations between ACE I/D, AGT M235T and PIH in Chinese populations. However, no significant association was found between ACE I/D and PIH in the subgroup of more than 100 cases. Studies with larger sample sizes are necessary to investigate the associations between gene polymorphisms and PIH in Chinese populations.