A fascinating new piece of research examining the human-animal bond and the genetic ties surrounding social behaviors of dogs and humans. Equally interesting: By analyzing behavioral and genetic data from dogs and gray wolves, researchers reported a strong genetic aspect to human-directed social behavior by dogs.
A common underlying genetic basis for social behavior in dogs and humans
Dogs’ ability to communicate and interact with humans is one the most astonishing differences between them and their wild cousins, wolves. A new study published today in the journal Science Advances identifies genetic changes that are linked to dogs’ human-directed social behaviors and suggests there is a common underlying genetic basis for hyper-social behavior in both dogs and humans.
An interdisciplinary team of researchers, including those from Princeton University, sequenced a region of chromosome 6 in dogs and found multiple sections of canine DNA that were associated with differences in social behavior. In many cases, unique genetic insertions called transposons on the Williams-Beuren syndrome critical region (WBSCR) were strongly associated with the tendency to seek out humans for physical contact, assistance and information.
In contrast, in humans, it is the deletion of genes from the counterpart of this region on the human genome, rather than insertions, that causes Williams-Beuren syndrome, a congenital disorder characterized by hyper-social traits such as exceptional gregariousness.
“It was the remarkable similarity between the behavioral presentation of Williams-Beuren syndrome and the friendliness of domesticated dogs that suggested to us that there may be similarities in the genetic architecture of the two phenotypes.”
-Dr. Bridgett vonHoldt, assistant professor in ecology and evolutionary biology at Princeton, study lead co-author
The researchers collected and analyzed the behavioral data for 18 domesticated dogs and 10 captive human-socialized wolves, as well as the biological samples used to sequence their genomes.
First, they quantified human-directed sociability traits in canines, such as to what extent they turned to a human in the room to seek assistance in trying to lift a puzzle box lid in order to get a sausage treat below or the degree to which they sought out social interactions with familiar and unfamiliar humans. Then, they sequenced the genome and correlated their findings…
Consistent with their hypothesis, the researchers confirmed that the domesticated dogs displayed more human-directed behavior and spent more time in proximity to humans than the wolves. The also discovered that some of these transposons on the WBSCR were only found in domestic dogs, and not in wolves at all…
…unlike previous research which suggests that, during the process of domestication, dogs were selected for a set of cognitive abilities, particularly an ability to discern gesture and voice, the current research posits that dogs were instead selected for their tendency to seek human companionship.
Journal Reference: Bridgett M. vonHoldt et al. Structural variants in genes associated with human Williams-Beuren Syndrome underlie stereotypical hyper-sociability in domestic dogs. Science Advances, 2017