The association between ACE I/D polymorphism and the risk of Alzheimer's disease in Lebanon

The insertion/deletion (I/D) polymorphism in Angiotensin converting enzyme (ACE) has been extensively studied as candidate gene for Alzheimer's disease (AD). In this study, the possibility of such an association was investigated in 83 patients diagnosed with AD and 80 matched controls from Lebanese origin. ACE I/D genotypes differed significantly between affected individuals and controls. In addition, ACE I allele and female gender were positively associated with increased risk of AD (O.R = 1.7, P = .02 and O.R = 4.2, P = .001, respectively). Furthermore, ACE I/D interacted with gender to influence the risk of AD (OR = 1.67, P = .001). When stratified according to gender and AD status, ACE I/D distribution varied significantly between AD and controls in women (P = .05) but not in men (P = .47). In conclusion, our study suggests that ACE I allele and female gender are associated with increased risk of AD in the Lebanese population.