Microglia - mediated immunity partly contributes to the genetic association between Alzheimer's disease and hippocampal volume

Lancaster, Thomas M. ORCID: https://orcid.org/0000-0003-1322-2449, Hill, Matthew J. ORCID: https://orcid.org/0000-0001-6776-8709, Sims, Rebecca ORCID: https://orcid.org/0000-0002-3885-1199 and Williams, Julie ORCID: https://orcid.org/0000-0002-4069-0259 2019. Microglia - mediated immunity partly contributes to the genetic association between Alzheimer's disease and hippocampal volume. Brain, Behavior, and Immunity 79 , pp. 267-273. 10.1016/j.bbi.2019.02.011

Preview

PDF - Accepted Post-Print Version Available under License Creative Commons Attribution. Download (1MB) | Preview

Abstract

Genome-wide association studies (GWAS) suggest that Alzheimer’s disease (AD) is partly explained by a burden of risk alleles (single nucleotide polymorphisms; SNPs) with relatively small effects. However, the mechanisms by which these loci cumulatively confer susceptibility remain largely unknown. Accumulating evidence suggests an association between increased AD risk allele burden (measured via a polygenic risk profile score; AD-RPS) with reduced hippocampal volume (HV) across a number of independent cohorts. These lines of research suggest that the reduced HV may be a causal mechanism of risk in the development of late-onset Alzheimer’s disease (AD). However, as RPS assesses broad, cumulative genetic risk, little is known about the biological processes which may explain this observation. Here, we leverage GWAS data from i) 17,008 late onset AD cases & 37,154 controls and ii) hippocampal volume (N = 12,147; N = 9707) to explore putative pathways that may explain this association. We first demonstrate an association between whole genome AD-RPS and HV (PT < 0.5, Z = −2.07, P = 0.038), confirming previous associations. Second, we restrict our analysis to SNPs within AD genes within a microglia mediated immunity network (NGENES = 56). A microglia AD-RPS was further associated with HV (PT < 0.01; Z = −2.152, P = 0.031). Last, using a competitive, permutation based approach, we show that the common variation within this candidate gene-set is associated with HV, controlling for SNP set-size (P = 0.024). Together, the observations suggest that the relationship between AD and HV is partially explained by genes within an AD-linked microglia mediated immunity network.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Medicine Cardiff University Brain Research Imaging Centre (CUBRIC) MRC Centre for Neuropsychiatric Genetics and Genomics (CNGG)
Publisher:	Elsevier
ISSN:	0889-1591
Date of First Compliant Deposit:	14 March 2019
Date of Acceptance:	14 February 2019
Last Modified:	25 Oct 2024 01:06
URI:	https://orca.cardiff.ac.uk/id/eprint/120686

Citation Data

Cited 10 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item