Dog domestication strongly relied on translation regulation according to differential gene expression analysis

Abstract The domestication of dogs from their shared ancestors with wolves occurred around 25,000 years ago and affected many characteristics of the species, including its appearance and behavior. Comparative RNA sequencing experiments can help shed light on the delicate details of gene expression regulation responsible for the variance in complex traits between dogs and wolves. Previously, Yang et al. identified the differentially expressed genes in the blood transcriptome of two Asian dogs and three wolves. We extended this study by adding ten European dog blood RNA-seq samples. The additional European samples made the analyzed dog cohort significantly more heterogenous, helping us avoid the detection of false positives. 40-120 million reads were aligned to the CanFam v3.1 reference genome per sample, ensuring high confidence in our results and conclusions. We detected approximately 14,000 expressed genes in the samples. Analyzing the sequence data, we found that the sample origin (Europe or Asia) had a significant effect on blood gene expression levels. Consequently, this was corrected for in the differential gene expression analysis model. We identified 1,807 differentially expressed genes between the two species and identified several significantly overrepresented gene ontology terms, such as rRNA binding, ribosomal large subunit biogenesis, and translation. Our functional gene ontology analysis implies that gene expression and regulation had a significant role in dog domestication. The findings suggest that further comparative studies between wolves and dogs should rely on a more diverse sample, including individuals from different breeds and geographical origins, to enhance the specificity of detecting differentially expressed transcripts between wolves and dogs.