Sleep and Late-Onset Alzheimer's Disease: Shared Genetic Risk Factors, Drug Targets, Molecular Mechanisms, and Causal Effects

Dongze Chen; Xinpei Wang; Tao Huang; Jinzhu Jia

doi:10.3389/fgene.2022.794202

Sleep and Late-Onset Alzheimer's Disease: Shared Genetic Risk Factors, Drug Targets, Molecular Mechanisms, and Causal Effects

Front Genet. 2022 May 17:13:794202. doi: 10.3389/fgene.2022.794202. eCollection 2022.

Authors

Dongze Chen¹, Xinpei Wang¹, Tao Huang^{2

3

4}, Jinzhu Jia^{1

5}

Affiliations

¹ Department of Biostatistics, School of Public Health, Peking University, Beijing, China.
² Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, China.
³ Key Laboratory of Molecular Cardiovascular Sciences (Peking University), Ministry of Education, Beijing, China.
⁴ Center for Intelligent Public Health, Institute for Artificial Intelligence, Peking University, Beijing, China.
⁵ Center for Statistical Science, Peking University, Beijing, China.

Abstract

Late-onset Alzheimer's disease (AD) is associated with sleep-related phenotypes (SRPs). The fact that whether they share a common genetic etiology remains largely unknown. We explored the shared genetics and causality between AD and SRPs by using high-definition likelihood (HDL), cross-phenotype association study (CPASSOC), transcriptome-wide association study (TWAS), and bidirectional Mendelian randomization (MR) in summary-level data for AD (N = 455,258) and summary-level data for seven SRPs (sample size ranges from 359,916 to 1,331,010). AD shared a strong genetic basis with insomnia (r _g = 0.20; p = 9.70 × 10^-5), snoring (r _g = 0.13; p = 2.45 × 10^-3), and sleep duration (r _g = -0.11; p = 1.18 × 10^-3). The CPASSOC identifies 31 independent loci shared between AD and SRPs, including four novel shared loci. Functional analysis and the TWAS showed shared genes were enriched in liver, brain, breast, and heart tissues and highlighted the regulatory roles of immunological disorders, very-low-density lipoprotein particle clearance, triglyceride-rich lipoprotein particle clearance, chylomicron remnant clearance, and positive regulation of T-cell-mediated cytotoxicity pathways. Protein-protein interaction analysis identified three potential drug target genes (APOE, MARK4, and HLA-DRA) that interacted with known FDA-approved drug target genes. The CPASSOC and TWAS demonstrated three regions 11p11.2, 6p22.3, and 16p11.2 may account for the shared basis between AD and sleep duration or snoring. MR showed insomnia had a causal effect on AD (OR_IVW = 1.02, P _IVW = 6.7 × 10^-6), and multivariate MR suggested a potential role of sleep duration and major depression in this association. Our findings provide strong evidence of shared genetics and causation between AD and sleep abnormalities and advance our understanding of the genetic overlap between them. Identifying shared drug targets and molecular pathways can be beneficial for treating AD and sleep disorders more efficiently.

Keywords: Mendelian randomization; common genetic etiology; genetic correlation; late-onset Alzheimer’s disease; sleep; transcriptome-wide association study.