Gene expression variability in human and chimpanzee populations share common determinants

Inter-individual variation in gene regulation has been shown to be heritable and it is quite often associated with differences in disease susceptibility between individuals. While many human studies focused on mapping associations between genetic and gene regulatory variation, 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 expression quantitative trait loci (eQTL) mapping study in humans and chimpanzees, using gene expression data from primary heart samples. While expression variability in both species is strongly determined by non-genetic sources, such as cell type heterogeneity, we found evidence that the degree of inter-individual variation in gene regulation is generally conserved in humans and chimpanzees. In particular, we found a significant overlap of genes associated with eQTLs in the two species. We conclude that humans and chimpanzees share sources common determinants of gene expression variability, including genetically regulated constraints from stabilizing and diversifying selection pressures. Overall design: 38 chimpanzee primary heart tissues samples subjected to RNA-seq. One replicate per individual. Analyzed in conjunction with previously published human primary heart tissue RNA-seq samples and chimpanzee samples in (Pavlovic et al. 2018 [PMID 30333510]). Only the 38 novel chimpanzee samples are included as raw data with this GEO project. Processed data also include a chimpanzee sample ("4x373") from which raw data was sourced from Pavlovic et al 2018 (GEO accession GSE110471)