How do dogs’ genes affect their behavior? Your pet could help scientists find out.

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Doberman pinschers are more prone than other dog breeds to compulsive behaviors like blanket-chewing. And in 2014, researchers unveiled some clues to a cause: Obsessive-compulsive disorder is in some dogs’ genes.

Studies like this that examine how DNA affects dogs’ behavior and thinking could, in theory, shed light on why some breeds have better memories than others, what genes make Labs so good at retrieving, or even what drives some dogs to bark at the UPS guy. Linking behaviors 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, have each in recent years founded their own companies. Boyko’s, Embark, is sort of like 23andMe for dogs, and it says it’s the highest-resolution DNA test for dogs on the market. Send in a swab of your dog’s drool and $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 $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 like 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 of America’s dogs to sign up for both products and participate in what they are billing “the largest canine behavioral genetics study to date.” In doing so, dog 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 said.

“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 behavior,” Hare said. “The reason we do not know about genes involved with brain and behavioral problems is there has never been a large scale study combining behavioral and genetic data on thousands of dogs.”

Hare and Boyko said 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 dogs’ 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 behaviors fundamental to dog domestication, “we can get some early insights into what made a dog a dog,” Boyko said.

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 behavior 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 said.

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 labeling 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, said 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 are bound to be dubious.

“If you want to do behavioral genetics, you need to be analyzing the behavior with a certain level of precision,” Wynne said. “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 behavior, personality and genes remains profoundly complicated, said Jessica Perry Hekman, a veterinarian and Ph.D candidate in behavioral genetics at the University of Illinois. But she said 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 behaviors than dogs raised in laboratories.

Hekman, for her part, named a different “Holy Grail” for the field: the creation of a genetic test for dog aggression, a goal she said 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 said.

“Maybe we’d be better able to understand which medications work and why and how,” she said. “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 behavioral 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 behavior 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, said Elinor Karlsson, a professor of bioinformatics and integrative biology who heads the project.

Karlsson has long worked on dog behavioral genetics – she was one of the researchers on the study of Dobermans and OCD – and usually relied on dogs that were patients at veterinary clinics. But she said she had trouble building statistically significant samples.

“I’m sitting there thinking, how can we possibly be having this problem? There’s millions of dogs out there in this country,” Karlsson said. At the suggestion of a veterinarian, she said, she realized, “we could ask owners how their dogs behave at home.”

With the help of canine behaviorists from the International Association of Animal Behavior Consultants, Karlsson and colleagues designed questionnaires that focus on well-established mental disorders as well as dog behaviors that have been selected by humans, such as retrieving. A third focus is on quirks that behaviorists 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 said.

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 said. “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, said Karlsson, who called the Embark and Dognition partnership “fantastic.”

“Even if behavior in dogs is way easier than behavior in humans, you’re still going to need thousands and thousands and thousands of dogs to get statistical power,” Karlsson said. “And the only way we’re going to be able to do it is to get dog owners to help us.”

(c) 2016, The Washington Post ยท Karin Brulliard

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