Two rare AKAP9 variants are associated with Alzheimer's disease in African Americans

Alzheimers Dement. 2014 Nov;10(6):609-618.e11. doi: 10.1016/j.jalz.2014.06.010. Epub 2014 Aug 27.

Abstract

Background: Less is known about the genetic basis of Alzheimer's disease (AD) in African Americans (AAs) than in non-Hispanic whites.

Methods: Whole exome sequencing (WES) was performed on seven AA AD cases. Disease association with potentially AD-related variants from WES was assessed in an AA discovery cohort of 422 cases and 394 controls. Replication was sought in an AA sample of 1037 cases and 1869 controls from the Alzheimer Disease Genetics Consortium (ADGC).

Results: Forty-four single nucleotide polymorphisms (SNPs) from WES passed filtering criteria and were successfully genotyped. Nominally significant (P < .05) association to AD was observed with two African-descent specific AKAP9 SNPs in tight linkage disequilibrium: rs144662445 (P = .014) and rs149979685 (P = .037). These associations were replicated in the ADGC sample (rs144662445: P = .0022, odds ratio [OR] = 2.75; rs149979685: P = .0022, OR = 3.61).

Conclusions: Because AKAP9 was not previously linked to AD risk, this study indicates a potential new disease mechanism.

Keywords: AKAP9; African American; Genetic association; Late-onset Alzheimer's disease; Rare variant; Whole-exome sequencing.

MeSH terms

  • A Kinase Anchor Proteins / genetics*
  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / ethnology*
  • Alzheimer Disease / genetics*
  • Black or African American / genetics*
  • Cluster Analysis
  • Cytoskeletal Proteins / genetics*
  • Female
  • Genetic Predisposition to Disease / genetics*
  • Genome-Wide Association Study
  • Genotype
  • Humans
  • Linkage Disequilibrium
  • Male
  • Polymorphism, Single Nucleotide / genetics*

Substances

  • A Kinase Anchor Proteins
  • AKAP9 protein, human
  • Cytoskeletal Proteins

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