Original Article by SHIRLEY S. WANG from Wall Street Journal can be read here.
The DNA of dogs may offer clues about human conditions, such as obsessive-compulsive disorder and autism, according to researchers at the University of Massachusetts Medical School, who have launched a major study of canine genetics, behavior and personality.
The team, led by Elinor Karlsson, a professor in the bioinformatics and integrative biology program, hopes that studying a large number of diverse breeds and mixed-breed dogs will yield more insight into the genetic underpinnings of certain traits and illnesses in dogs, and one day lead to improved medical treatments for humans. Humans and canines share almost all the same genes and suffer from many of the same diseases.
Other scientists, including Brian Hare at Duke University, are focusing on pets and pet owners, investigating canine cognition to learn more about how both dogs and humans think and learn.
Dogs are a better natural model for some human diseases than mice or even primates because they live with people, Dr. Karlsson says. “Compared to lab mice, with dogs they’re getting diseases within their natural life span, they’re exposed to the same pollutants in the environment” as humans, she says.
Previous canine studies conducted by other scientists have shed light on human diseases like osteosarcoma, a type of bone cancer, as well as the sleep disorder narcolepsy and a neurological condition, epilepsy.
With osteosarcoma, the most common type of bone cancer in children and one that frequently strikes certain dog breeds, researchers have discovered that tumors in dogs and children are virtually indistinguishable. The tumors share similarities in their location, development of chemotherapy-resistant growths and altered functioning of certain proteins, making dogs a good animal model of the disease. Collecting more specimens from dogs could lead to progress in identifying tumor targets and new cancer drugs in dogs as well as in children, some scientists say.
Dr. Karlsson and her team at the University of Massachusetts, in collaboration with the International Association of Animal Behavior Consultants, hope to expand canine genetic discoveries with their project, launched in October and dubbed Darwin’s Dogs. Rather than focus on specific breeds and on DNA collected by scientists, the researchers are asking pet owners to share observations about their pets’ behaviors and personalities and to collect DNA at home via mouth swabs, similar to the way consumer genetics companies collect DNA.
Dr. Karlsson hopes the collective genetic and behavioral canine data will help elucidate psychiatric conditions.
She began her work on dog genes as a graduate student, when she helped map out which genes were responsible for coat color in boxers and bull terriers. The classic genetics research, published in Nature Genetics in 2007, showed that a technique called genome-wide association mapping, often known as GWAS, could be used within dog breeds to look broadly across genes for links with a condition or characteristic of interest.
Later, as a post-doctoral researcher, Dr. Karlsson worked with a team studying Dobermans and their high rates of a condition known as canine compulsive disorder. It is similar to humans’ obsessive-compulsive disorder, or OCD, which is defined as doing an otherwise normal behavior much too frequently. In the case of Dobermans, the behavior was chewing on their sides or on blankets.
Canine compulsive disorder starts in around early- to mid-adolescence—at about the same age as in humans and likely with similar neurological processes. Humans and dogs with compulsive disorders are treated with the same drugs, and among those treated with the drugs only 50% respond, Dr. Karlsson says.
The team studied genes of hundreds of Dobermans with and without canine compulsive disorder and initially identified one gene associated with the compulsive condition in the breed—called CDH2, the gene is thought to be important in human OCD—and later identified genetic mutations near CDH2.
Then the researchers looked at other dog breeds and found more genes linked to OCD and all tied into the same pathway in the brain, in a study published last year in Genome Biology. The team aims to look more closely at the genetics of compulsive behaviors and expand to other psychiatric conditions, which could lead to new targets for treatment.
Dr. Hare, a professor in the department of evolutionary anthropology at the Duke University Institute for Brain Sciences, is taking a similar approach with canine cognition.
Drawing on some methods used to test human infants, such as having babies complete various tasks while researchers observe and draw conclusions from the behavior, Dr. Hare began thinking about the millions of U.S. dog owners and all the data that could be collected if they were recruited to help with research. In 2013, he founded a company, Dognition, which tells pet owners they can be “citizen scientists” by getting their dogs to complete games, or experimental tasks.
In an exercise called the “memory vs. pointing task,” the owner shows the dog where a treat is hidden, then points in the opposite direction. The owner sees whether the dog goes to the treat, relying on his own memory, or if he heads in the direction where the owner pointed, suggesting he is more reliant on people than on independent problem solving.
Dr. Hare and his team have tested the validity of data collected from owners at home compared with that of data collected in the lab and found they were comparable—suggesting citizen-scientist data is useful and reliable, according to a paper they published in September in the journal Plos One.
The data tends to be interesting for pet owners, who often want to know how their dog’s results compare with other dogs’, says Dr. Hare. But as with any behavioral research, it can be difficult to know if behaviors and the motivation for behaviors are interpreted correctly, says Marji Alonso, executive director of the International Association of Animal Behavior Consultants, who is collaborating with the Massachusetts group.
Unpublished data from Dognition suggests that dogs experience cognitive decline, a phenomenon that hasn’t previously been established, Dr. Hare says. If the corresponding owner also develops cognitive decline, questions arise about whether there are environmental or behavioral factors affecting both human and canine, Dr. Hare says—an inquiry that is central to the idea of “one health,” or how animal research can help human health and vice versa. “One health is this fantastic opportunity,” Dr. Hare says. “By helping animals, you’re actually helping us.”