Are dogs’ personalities hardwired into their DNA?
When we think of certain dog breeds, specific characteristics come to mind: Beagles are boisterous. Afghans are aloof. Pembroke Welsh Corgis are sycophantic and suck up to royalty (not really).
But it’s well documented that different breeds have different personalities. Are those differences determined by DNA?
A new study suggests that the answer is yes, at least partially. And the findings could be a clue to better understanding the link between genetic markers and human behaviors.
So say coauthors Evan MacLean, PhD, director of the Arizona Canine Cognition Center at the University of Arizona, and Noah Snyder-Mackler, PhD, assistant professor of psychology at the University of Washington.
Their study states that dogs were chosen as test subjects due to their “simplified genetic architecture,” a result of the selective breeding used to develop different breeds. The researchers analyzed a combined behavior dataset of more than 17,000 dogs comprised of 101 different breeds, including Doberman pinschers, Labrador retrievers, and border collies.
When the researchers compared that data to genetic breed data from a different group of dogs, they identified 131 sites in a dog’s DNA that appeared to be connected to 14 behavioral traits. These DNA regions account for about 15% of a dog’s personality.
The researchers also discovered that certain genetically linked traits in dogs were similar to genetically linked traits in humans.
For example, breed differences in canine aggression are associated with multiple genes that have been linked to aggressive behavior in humans; breed differences in energy include genes linked to resting heart rate, daytime rest, and sleep duration in humans; and breed differences in fear were associated with genes linked with temperament and startle response in humans.
Interestingly, several of the genes linked to breed differences in trainability have been associated with intelligence and information processing speed in humans.
MacLean told NEWStat, “The most heritable traits we found were trainability, stranger-directed aggression, attachment, attention seeking, [and] chasing.”
The study notes that these traits are “consistent with the hypothesis that these behaviors have been important targets of selection during the cultivation of modern breeds.” (i.e., the traits most desired by pet owners.) MacLean added that the least heritable were nonsocial fears and dog-directed fears.
But people who want to know if their Pembroke Welsh corgi is more or less likely than Her Majesty the Queen of England’s Pembroke Welsh corgi to inherit, say, stranger-directed aggression, are out of luck; MacLean says the study didn’t address heritability within breeds: “All we know at the moment is the broad extent to which genetic similarity between breeds explains behavioral differences between breeds.”
MacLean says breeding selectivity and evolutionary selectivity are very similar processes: “Both artificial [breeding] and natural selection create change through differential survival and reproduction of certain forms. If a variant is selected either because it helps an animal to survive and reproduce in nature, or because humans value that trait and selectively choose those animals to breed, over time you get evolution within the population. The main difference is whether this is determined by an animal’s natural ability to survive and reproduce, or if humans play a hand. In either case, if the selection pressure is intense, change can occur very quickly.”
MacLean things that further research in this area could have practical applications in veterinary medicine.
“I think a critical first step in any kind of treatment is understanding the biological and environmental contributions to what you’re looking at,” says MacLean. “Like all things, behavior is both nature and nurture. If we can identify the relevant genes and biological pathways, then this may provide a hint as to how we could develop interventions to target certain kinds of problematic behavior.”