Gut Bacteria from Wild-Type Mice Fix Social Deficit of Cntnap2 Knockout Mice
A preview of an upcoming study from scientists at the University of Geneva in Switzerland has shown that microorganism transfer into the microbiomes of rodents can influence their social behavior. This short report begins by explaining the hologenome theory, which suggests that a host’s genetic information is complemented by the genetic information of all symbiotic microorganisms. This theory also proposes that the host and the symbiotic microbes act as a single biological entity. These Swiss researchers had the hologenome theory in mind when they decided to explore the effect of gut microbiota on social behavior. In order to do this, the team took Cntnap2 (a gene coding for a neurexin-like adhesion molecule) knockout (KO) mice and kept them in homozygous isolation. (Lack of Cntnap2 has been loosely associated with autism.) The isolated KO mice exhibited behavioral abnormalities like enhanced spontaneous locomotion and a lack of interest in their fellow KO mice. Additionally, the KO mice’s microbiome differed from wild-type (WT) mice. The researchers then introduced the KO mice to WT mice and housed them together. After putting these two types of mice together, the KO mice’s microbiota mirrored the microbiota of the WT mice. Then something interesting happened, the KO mice lost their abnormal behaviors and became more social. The study’s authors hypothesize that their rodent study has implications for children with autism who often suffer from gastrointestinal disorders and have low levels of some bacterial species in their GI tract. They call for more development of microbiota-based therapeutic interventions in the future with the hopes it may ease other autism related symptoms like antisocial behavior.
