Gene expression variability in human and chimpanzee populations share common determinants
- University of Chicago, United States
- University of California, San Francisco, United States
Abstract
Inter-individual variation in gene expression has been shown to be heritable and is often associated with differences in disease susceptibility between individuals. Many studies focused on mapping associations between genetic and gene regulatory variation, yet much less attention has been paid to the evolutionary processes that shape the observed differences in gene regulation between individuals in humans or any other primate. To begin addressing this gap, we performed a comparative analysis of gene expression variability and expression quantitative trait loci (eQTLs) in humans and chimpanzees, using gene expression data from primary heart samples. We found that expression variability in both species is often determined by non-genetic sources, such as cell-type heterogeneity. However, we also provide evidence that inter-individual variation in gene regulation can be genetically controlled, and that the degree of such variability is generally conserved in humans and chimpanzees. In particular, we found a significant overlap of orthologous genes associated with eQTLs in both species. We conclude that gene expression variability in humans and chimpanzees often evolves under similar evolutionary pressures.
Data availability
RNA-Seq data available under GEO accession number GSE151397. Raw whole genome sequencing data under SRA accession PRJNA635393. Processed whole genome sequencing data available as variant calls at European variation archive, EVA accession PRJEB39475.
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Gene expression variability in human and chimpanzee populations share common determinantsNCBI Gene Expression Omnibus, GSE151397.
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A Comparative Assessment of iPSC Derived Cardiomyocytes with Heart Tissues in Humans and ChimpanzeesNCBI Gene Expression Omnibus, GSE110471.
Article and author information
Author details
Benjamin Jung Fair
Funding
National Institute of General Medical Sciences (R35GM131726)
- Yoav Gilad
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Fair et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Gene expression variability in human and chimpanzee populations share common determinants
eLife 9:e59929.
https://doi.org/10.7554/eLife.59929
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