Certain dog breeds, including German shepherds, Doberman pinschers, and Shetland sheepdogs are prone to high rates of obsessive-compulsive disorder (OCD), including licking their paws to the point of injury. Scientists have suspected that some of the same genetic mechanisms might lie within compulsions in people, including repetitive behaviors or intense stress when objects are not in the right order.
Researchers from the Broad Institute in Massachusetts and Uppsala University in Sweden found 4 genes with changes that were present in dogs with OCD, but not in a comparison group of greyhounds and Leonbergers or “Lion Dogs,” neither of which have high rates of canine OCD. The 4 genes are involved in forming and regulating synapses, which are connections between brain cells that let them transmit information.
Co-senior author Elinor Karlsson, Ph.D., a postdoctoral fellow at the Broad Institute and at the Center for Systems Biology at Harvard says that when thousands or millions of cells are connected this way they form a brain circuit. Scientists believe that dogs with OCD and perhaps for humans with OCD as well, the circuit that tells us when a task is complete, for example is possibly broken.
“Basically, maybe there’s no message being sent that says a task is completed, it’s time to stop,” Karlsson says.
“Dogs have a simpler genetic architecture, and that simpler architecture gives us a lot of really important clues about human OCD,” says co-first author Hyun Ji, Ph.D., also of the Broad Institute.
“The right treatment is effective, but there are barriers to treatment such as stigma and misdiagnosis. I’m extremely organized so I keep my desk neat because I want to, but a person with OCD has intense anxiety, time-consuming and embarassing compulsive behaviors that they know are irrational and don’t want to do, but can’t stop,” says executive director, Jeff Szymanski, Ph.D., executive director at the international OCD Foundation in Boston, Ma.
Says Karlsson, “dogs are a really powerful model for us, and eventually the hope is to help both dogs and humans with OCD. We owe a big debt of gratitude to the dogs and their humans who send in the DNA.”
The new research will be published soon in the online journal Genome Biology………….. nbcnews.com 2/25/14