The genetics of functional decline in the aging vestibular system: A GWAS and gene expression analysis in aging mice and humans

NIH RePORTER · NIH · R01 · $797,187 · view on reporter.nih.gov ↗

Abstract

Fall-related injury in the elderly carries a 20% mortality rate, and is the sixth leading cause of death in this population. Age-related dysfunction of gravity receptors within the vestibular system is highly correlated with these elderly falls, and significant age-related degeneration is associated with nearly all types of vestibular cells. The overarching goal of this study is to analyze human and mice genome-wide association studies (GWAS), vestibular-specific human and mice genomic expression, and single-cell sequencing of specific sites in the vestibular system, then test identified genes and related pathways in the lab. Our objective is to characterize the genomics related to age-related imbalance for future prevention and treatment. The central hypothesis is that by this analysis, we can identify anatomic and physiologic sites relevant to the balance system that is common to both species. Our rationale is that by this analysis, we can better focus on relevant genes and pathways for lab testing and ultimate therapeutic intervention. Building upon a small GWAS on elderly falls that correlated human DCC and PTK2 genes in the same pathway as Dcc identified in the Hybrid Mouse Diversity Panel (HMDP) GWAS, our specific aims will be: 1) a. Perform GWAS in humans based on a dizziness/falls phenotype in a meta-analysis of large datasets; b. GWAS in mice based on a behavioral and gravity sensor function phenotype in the HMDP; 2) a. Perform RNA-Sequencing on vestibular tissues from mice and human surgical specimens; b. Single-cell RNA-Seq on individual tissues; c. Compare identified genes and pathways via computational methods to assess translation of pathways from the mouse to human balance system; and 3) Perform functional testing for the top candidates defined in Aim 2 using knock-out/knock-in mice. Multiple innovations of this project include: 1) the first GWAS of gravity receptor function in aged mice and in elderly humans, 2) a comprehensive catalogue of genes and pathways involved in vestibular functional variation with inter-species comparison, as part of FAIR (findable, accessible, interoperable, reusable) Compliance, 3) in vivo validation in mouse models and an analysis of these candidates in available human cohorts, and 4) future potential for targeted therapies. Our outcome is the first comparative GWAS of the balance system between animal models and humans. The impact of this work will be to lay a firm foundation for development of targeted treatment of the balance system to diminish falls in the elderly.

Key facts

NIH application ID
10633162
Project number
5R01DC020052-03
Recipient
UNIVERSITY OF CALIFORNIA, SAN DIEGO
Principal Investigator
Royce Ellen Clifford
Activity code
R01
Funding institute
NIH
Fiscal year
2023
Award amount
$797,187
Award type
5
Project period
2021-09-01 → 2026-05-31