Meta-Analysis of Aldehyde Dehydrogenase 2 Gene Polymorphism and Alzheimer's Disease in East Asians

Abstract

Background:The association of genetic polymorphism of mitochondrial aldehyde dehydrogenase 2 (ALDH2) and Alzheimer's disease (AD) has been controversial and has been investigated only in several small-sample studies. In the present study, we performed a meta-analysis to evaluate the cross-sectional association ofALDH2variants and AD risk in East Asian populations.Methods:Trials were retrieved through MEDLINE, EMBASE, J-STAGE and the China National Knowledge Internet databases (from January 1, 1994 to November 1, 2010) without any restriction on language. Data were abstracted by a standardized protocol.Results:We found four studies of 821AD patients and 1380 healthy controls that qualified for the analysis. The variantALDH2genotype GA/AA was not associated with increased AD risk (odds ratio (OR) = 1.35; 95% confidence interval (CI) = 0.75-2.42; p = 0.32), even after stratification for the status of apolipoprotein E epsilon 4 allele. However, in the subgroup analyses, the association was significant for men (OR = 1.72; 95% CI = 1.10-2.67; p = 0.02).Conclusions:This study adds to the evidence thatALDH2GA/AA genotype increases the risk of AD among East Asian men, although the effect size is moderate.