Association study and meta-analysis of Alzheimer's disease risk and presenilin-1 intronic polymorphism.

Numerous studies have tested for associations between an intronic polymorphism (rs165932) of presenilin-1 (PS-1) gene and the risk of Alzheimer's disease (AD), but results have been conflicting. To throw light on this issue, we investigate the possible involvement of PS-1 genotype in a case–control study based on a relatively stable population in Spain and a meta-analysis of published studies. An examination was conducted of 85 patients with probable or possible AD, along with controls from the same community, by using an χ 2 test for homogeneity and a binary logistic regression model. For comparison purposes, a meta-analysis of data from all available published studies was assessed. In our patients, homozygosity of the allele 2 in the PS-1 gene increased for late-onset AD (OR 2.38, 95% CI 1.07–5.29, P p p