Associations of Angiotensin-Converting Enzyme Gene Insertion/Deletion (ACE Gene I/D) Polymorphism With Vitiligo: An Updated Systematic Review and Meta-Analysis.

Objective The objective of the article is to summarize the current evidence regarding the association between angiotensin-converting enzyme insertion/deletion (ACE I/D) gene polymorphism and vitiligo disease. Methods A computerized search was performed through four electronic databases (PubMed, Scopus, Cochrane Central Register of Controlled Trials [CENTRAL], and Web of Science) with the relevant keywords. Included studies comprised of papers examining the association of ACE gene polymorphisms with vitiligo. Data were pooled as an odds ratio (OR) in random- and fixed-effect models using the Mantel-Haenszel (M-H) method. Review Manager 5.3 software (clicktime.com, Inc., San Francisco, US) was utilized in the meta-analysis.  Results Ten studies (n=2,740) matching the inclusion criteria were included in the systematic review and meta-analysis. Results showed no significant difference between individuals carrying deletion/deletion (D/D) genotype and individuals with deletion/insertion (D/I) + insertion/insertion (I/I) genotypes in terms of vitiligo risk (odds ratio [OR]=1.13, 95% confidence interval [CI]: 0.78 to 1.64, p=0.53). However, vitiligo risk was higher in the individuals carrying the I/D genotype when compared with individuals with D/D + I/I genotypes (OR=1.29, 95% CI: 1.10 to 1.52, p=0.001). Moreover, the increased risk was observed in individuals carrying D/D when compared with I/I (OR=1.67, 95% CI: 1.33 to 2.09, p<0.0001). D allele was associated with significant risk when compared with the I allele (OR=1.29, 95% CI: 1.15 to 1.45, p<0.0001). Conclusion The current evidence suggests that there is a significant association between ACE I/D gene polymorphism and vitiligo. These findings support the use of ACE polymorphism in the prediction of vitiligo as a biomarker.