The Association between Polygenic Hazard and Markers of Alzheimer's Disease Following Stratification for APOE Genotype

Curr Alzheimer Res. 2020;17(7):667-679. doi: 10.2174/1567205017666201006161800.

Abstract

Background: Research indicates that polygenic indices of risk of Alzheimer's disease are linked to clinical profiles.

Objective: Given the "genetic centrality" of the APOE gene, we tested whether this held true for both APOE-ε4 carriers and non-carriers.

Methods: A polygenic hazard score (PHS) was extracted from 784 non-demented participants recruited in the Alzheimer's Disease Neuroimaging Initiative and stratified by APOE ε4 status. Datasets were split into sub-cohorts defined by clinical (unimpaired/MCI) and amyloid status (Aβ+/Aβ-). Linear models were devised in each sub-cohort and for each APOE-ε4 status to test the association between PHS and memory, executive functioning and grey-matter volumetric maps.

Results: PHS predicted memory and executive functioning in ε4ε3 MCI patients, memory in ε3ε3 MCI patients, and memory in ε4ε3 Aβ+ participants. PHS also predicted volume in sensorimotor regions in ε3ε3 Aβ+ participants.

Conclusion: The link between polygenic hazard and neurocognitive variables varies depending on APOE-ε4 allele status. This suggests that clinical phenotypes might be influenced by complex genetic interactions.

Keywords: Mild cognitive impairment; amyloid; apolipoprotein; executive function; memory; polygenic traits.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / diagnostic imaging*
  • Alzheimer Disease / genetics*
  • Apolipoprotein E4 / genetics*
  • Cohort Studies
  • Female
  • Genetic Markers / genetics*
  • Genotype*
  • Humans
  • Magnetic Resonance Imaging / methods
  • Male
  • Middle Aged
  • Multifactorial Inheritance / genetics*

Substances

  • Apolipoprotein E4
  • Genetic Markers