Effects of Cognitive- and Sleep- Related Single Nucleotide Polymorphisms on Cognitive Functions in the Han Chinese Community-dwelling Elderly

Objective: The genetic biomarkers on Alzheimer’s disease (AD) have been widely studied in different groups. Since the lack of efficacy therapeutic methods for AD, early recognition in preclinical stage becomes increasingly important. Evidence of AD and cognitive-related single nucleotide polymorphisms (SNPs) in high risk population is insufficiency. Our aim was to assess whether these SNPs within cognitive- and sleep- associated genes are correlated with cognitive impairment independently or through gene-gene interactions in community-dwelling elderly in Beijing. Methods: Eight single-nucleotide polymorphisms (SNPs) were genotyped in 2133 Northen Han Chinese elderly from ten communites in Chaoyang District, Beijing. The short version of the Montreal Cognitive Assessment-Beijing (MoCA-s), Ascertain Dementia 8 (AD8), Digit Span Backwards (DSB), Digital Symbol Substitution Test (DSST), and Paired Associative Learning Test (PALT) were used to detect different cognitive domains.Results: Logistic regression analyses showed a significant correlation between APOE (rs429358), ABCC9 (rs11046205) and cognitive impairment, and an interaction between ABCC9 (rs11046205)/APOE promoter (rs405509) and APOE ε4 status. Additionally, we found a significant negative association between the additive model of APOE (rs429358) and MMSE score. Moreover, our analysis revealed that the gene-gene interaction between ABCC9 (rs11046205) and APOE (429358) may contribute to the etiology of congnitive impairment.Conclusions: This study confirmed the independent contribution of AD, memory and sleep-related genes in the cognitive impairment of the community-dwelling elderly in China, as well as through gene-gene interactions.