The composition of the human gut microbiome is determined by environmental influences. For example, diet and medication are well established factors that influence these microbial ecosystems. However, the contribution of genetics has been more difficult to ascertain. And what is the impact of people that we interact with socially? Now, a study involving more than four thousand animals, reveals that the composition of the rat gut microbiome is shaped not only by an individual’s own genes but also by the genes of the individuals they share a living space with. This work is published in Nature Communications in the paper, “Genetic architecture and mechanisms of host-microbiome interactions from a multicohort analysis of outbred laboratory rats.” The work uncovers that the exchange of commensal gut microbes that move between individuals is a new path where genes and social life intertwine. Although genes don’t jump between individuals, microbes can. The study found some genes favor certain gut bacteria and these can spread through close social contact. “This is not magic, but rather the result of genetic influences spilling over to others through social contact,” explained Amelie Baud, PhD, group leader at the Centre for Genomic Regulation (CGR) in Barcelona. “Genes shape the gut microbiome and we found that it is not just our own genes that matter.” In this study, the rats used are genetically unique and come from one of four different cohorts, each housed in a different facility in the United States and with different care routines, allowing the researchers…
