The ACE Alu polymorphism contributes to neovascular AMD risk

Abstract

Abstract: : Purpose:Age–related macular degeneration (AMD) is the leading cause of blindness in the elderly population in the developed world. We report a statistically significant association between the angiotensin converting enzyme (ACE) polymorphism and wet AMD. Methods: Using the polymerase chain reaction we amplified a polymorphic region in the ACE gene on total genomic DNA collected from AMD and control patients. AMD classification was based on slightly modified criteria from the international Age Related Maculopathy study group. Results:We found a significant excess of the ACE Alu+ allele in wet AMD (n=67; Chi square=4.2, d.f. =1, p=0.039) compared with dry AMD (n=24). This yielded an odds ratio (OR) of 2.0 (95% CI=1.0–4.0). Conclusions: The ACE polymorphism has been previously associated with lower ACE activity in the bloodstream and in tissues. We have also previously shown that lower ACE activity enhances retinal endothelial cell survival in tissue culture. We hypothesize that the Alu+ allele leads to an enhancement in endothelial cell survival by ACE inhibition leading to a predisposition for neovascular AMD.

Keywords: age–related macular degeneration • genetics • neovascularization