How do dogs’ genes affect their behaviour? Your pet could help scientists find out
Researchers turn to dog owners for their input in ‘the largest canine behavioural genetics study to date’ aimed at discovering what makes man’s best friend tick
Doberman pinschers are more prone than other dog breeds to compulsive behaviours such as blanket chewing. And in 2014, researchers unveiled some clues to a cause: obsessive-compulsive disorder is in some dogs’ genes.
Such studies that examine how DNA affects dogs’ behaviour and thinking could, in theory, shed light on why some breeds have better memories than others, what genes make Labradors so good at retrieving, or even what drives some dogs to bark at the postman. Linking behaviours to genes is simpler in dogs than in humans: thanks to generations of selective breeding, dog DNA is far less variable than ours.
Even so, there are obstacles to doing this research well. Scientists need a lot of information on how dogs behave or how well they perform in intelligence tests, and they also need to collect their DNA. For statistical power, they need to do it in thousands of dogs. Doing that in a laboratory would take loads of time – and sequencing DNA takes loads of money.
Now some prominent scientists are going about it from a new direction – by asking ordinary dog owners for help.
Adam Boyko, a dog geneticist at Cornell University, and Brian Hare, a canine cognition researcher at Duke University, both in the US, have each in recent years founded their own companies. Boyko says his Embark is the highest-resolution DNA test for dogs on the market. Send in a swab of your dog’s drool and US$199 and you get a report that breaks down the pup’s breed and ancestry, as well as its risk for dozens of genetic diseases. Hare’s company, Dognition, charges fees starting at US$19 for Web-based cognition tests – “interactive games” that can involve hiding treats under cups – that dog owners perform with their pets. Owners get a report outlining how their dog rates on traits such as empathy and memory, as well as a personality profile such as “Einstein” or “Socialite”.
Recently, the two teamed up in hopes of getting 5,000 dog owners to sign up for both products and have their pets participate in what they are billing “the largest canine behavioural genetics study to date”. In doing so, owners act not only as research assistants and research funders, but also help build a database that could yield “genetic insight into what makes dogs tick”, Boyko says.
“We know a lot more about the bodies of our dogs and how they can break down, more than what we know about their brains and behaviour,” Hare says. “The reason we do not know about genes involved with brain and behavioural problems is there has never been a large-scale study combining behavioural and genetic data on thousands of dogs.”
Hare and Boyko say they plan to make their data available to other scientists with the goal of answering some of those questions. Embark, for example, looks at whether dog genomes have a common genetic variant found in wolves, dogs’ wild ancestors, and assigns dogs a “wolfiness score”. By comparing that with Dognition data, which probe behaviours fundamental to dog domestication, “we can get some early insights into what made a dog a dog”, Boyko says.
That, in Hare’s words, “is from a scientific perspective the Holy Grail”. But it could also help dog owners better understand their dogs. Dogs are frequently taken to vets or surrendered for behaviour issues, and knowing whether they’re rooted in genetics could help owners tailor training or decide whether a dog is best suited to being a guard dog rather than a family pet, Boyko says.
That’s the idea, anyway. Not all dog scientists are sold on the idea that this sort of canine crowdsourcing approach is useful. Some fault Dognition’s matter-of-fact labelling of a dog’s traits based on cognition tests, because they say the science behind what those tests reveal is hardly clear.
Clive Wynne, a psychologist who directs Arizona State University’s Canine Science Collaboratory, says he believes charging participants could lead to skewed samples heavy on privileged dogs, and that data collected by pet owners in uncontrolled living-room settings is bound to be dubious.
“If you want to do behavioural genetics, you need to be analysing the behaviour with a certain level of precision,” Wynne says. “I’ve never heard it suggested that you could achieve that level of precision by letting everybody do tests on their own dog.”
Hare disputes that, noting that he and colleagues compared Dognition’s dog-owner data with lab-collected data and found they were similar. In 2015, they published their findings in a paper that argued “citizen scientists will generate useful datasets”.
Even in dogs, determining links between behaviour, personality and genes remains profoundly complicated, says Jessica Perry Hekman, a vet and PhD candidate in behavioural genetics at the University of Illinois. But she says the Dognition-Embark effort and others like it are “the next thing to try”, in part because dogs tested in homes probably display more typical behaviours than dogs raised in laboratories.
Hekman, for her part, names a different “Holy Grail” for the field: the creation of a genetic test for dog aggression, a goal she says is very far off. Identifying the genetic underpinnings of aggression, fear or compulsiveness and using that to see how those affect brain processes is more realistic, she says.
“Maybe we’d be better able to understand which medications work and why and how. That really is a much more graspable goal.”
Another effort, based at the University of Massachusetts Medical School, is also using a citizen-science approach to dog behavioural genetics. Participants in Darwin’s Dogs, as it is known, swab their dog’s mouth for DNA and answer more than 120 survey questions about their dog’s behaviour and personality. There’s no fee – this project is funded by the university and the National Institutes of Health – but participants also get no immediate results.
That hasn’t deterred dog owners, nearly 11,000 of whom have signed up, says Elinor Karlsson, a professor of bioinformatics and integrative biology who heads the project. Karlsson has long worked on dog behavioural genetics – she was one of the researchers on the study of Dobermans and OCD.
With the help of canine behaviourists from the International Association of Animal Behaviour Consultants, Karlsson and colleagues designed questionnaires that focus on well-established mental disorders as well as dog behaviours that have been selected by humans, such as retrieving. A third focus is on quirks that behaviourists told Karlsson some breeds display more than others but that wouldn’t have resulted from training. Examples: sleeping belly up, eating grass and “that adorable head tilt”, Karlsson says.
But there’s a more serious side to the project. Dogs and people have similar genes and diseases, so findings in dogs could lead to treatments for people.
“We know that psychiatric diseases in humans and dogs have a big genetic component. They’re very heritable,” Karlsson says. “We’re trying to understand in much more detail what exactly are the pathways of the brain that are involved in these diseases.”
Eventually, Darwin’s Dogs’ data will be shared broadly among researchers, says Karlsson, who calls the Embark and Dognition partnership “fantastic”.
“Even if behaviour in dogs is way easier than behaviour in humans, you’re still going to need thousands and thousands and thousands of dogs to get statistical power,” Karlsson says. “And the only way we’re going to be able to do it is to get dog owners to help us.”