Objective: To study on the association of M235T polymorphism of the angiotensinogen gene extron 2 (AGT/M235T) and essential hypertension (EH) in Chinese population by means of Meta-analysis.
Methods: Odds ratios (OR) of AGT M235T genotype distributions in EH patients against healthy controls were analyzed. All the relevant studies were identified, poor-qualified studies eliminated, and the risk of publication bias excluded. The Meta-analysis software, REVMAN4.1, was applied for investigating heterogeneity among individual studies and summarizing the effects across studies.
Results: A total of 853 cases and 835 controls from 10 studies were included. No heterogeneity among the studies was noticed. The frequencies of the AGT TT, MT and MM genotypes were 65%, 30%, and 4.9% in cases and 50.6%, 41.8% and 7.5% in controls respectively. The frequencies of the AGT T allele were 80% in cases and 72% in controls. The pooled OR (with 95% CI) of TT vs MT + MM was 1.76 (1.44 - 2.16) (P < 0.000 01) with T vs M 1.54 (1.31 - 1.81). The pooled OR of MM vs MT + TT was 0.67 (0.45 - 1.00) (P = 0.05).
Conclusion: In Chinese population (mainly the Hans), TT genotype might be associated with the increased risk of EH while MM genotype be associated with low risk of EH.