Angiotensin-I Converting Enzyme Gene Polymorphisms and the Risk of Venous Thromboembolism in an Ethnically Chinese Population Living in Taiwan

Background: There have been conflicting reports of the association between the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene, and the risk of venous thromboembolism (VTE). We sought to investigate the association between ACE I/D polymorphism, and the risk of VTE in a Chinese population living in Taiwan. Methods: 176 patients with VTE and 321 age and sex-matched controls were analyzed for the ACE I/D polymorphism by polymerase chain reaction. Results: The genotype distribution of the ACE I/D polymorphism was not statistically different between the VTE affected subjects and the group of unaffected subjects (p = 0.057). Notably, the frequency of ACE D allele in patients with VTE were significantly lower than that in the control group (28% vs. 35%, p = 0.018). After adjusting for age, gender, smoking, hypertension, diabetes and body mass index (BMI), the ACE D allele carriers remained significantly associated with a decreased risk of VTE. Further meta-analysis by pooling data from 15 studies revealed that neither the DD, nor the II genotype, was found to be associated with VTE (pooled unadjusted odds ratio were 1.167, 95% confidence intervals, 0.927-1.470, p = 0.189 for DD, and 1.085, 95% confidence intervals, 0.875-1.345 p = 0.460 for II). Conclusion: Our results suggest that the presence of the D allele may confer protection against the development of VTE in an ethnically Chinese population in Taiwan. Further meta-analysis did not support a relationship between the ACE I/D polymorphism and the risk of VTE.