The butyrylcholinesterase K variant is a protective factor for sporadic Alzheimer's disease in women

Abstract

Introduction– Recent reports indicate that the K variant of the butyrylcholinesterase (BCHE) gene may act in synergism with the ε₄ allele of apolipoprotein E (APOE) to increase the risk of Alzheimer's disease (AD), but this is controversial. Material and methods– We genotyped for the BCHE‐K and APOE ε₄ alleles in a sample of 249 AD patients and 250 controls derived from the same region in a Spanish population. Results– A protective effect of the K variant of BCHE with an odds ratio of 0.41 (95% confidence interval 0.19–0.86, P=0.02) was observed among non‐APOE ε₄ carriers, but it was limited to women. Conclusion– Our study is the first to demonstrate that lower susceptibility to AD determined by the K variant of BCHE is dependent on gender.