Compulsive behavior gene discovered in dogs

Grafton, Mass.

-- Researchers at Tufts University's Cummings School of Veterinary Medicine pinpointed a location on the canine chromosome that could help identify dogs at higher risk for compulsive behavior disorder.

For more than 10 years, Cummings faculty members Drs. Nicholas Dodman and Alice Moon-Fanelli have collected blood samples from Dobermans, a breed predisposed to compulsive behavior. They drew samples from both healthy, unaffected Dobermans, as well as dogs that displayed behaviors like sucking on blankets and/or their own flanks. Study of the samples at the University of Massachusetts Medical School led to this genetic discovery.

Dobermans showing multiple compulsive behaviors had a higher frequency of a risk-associated DNA sequence on chromosome 7 on the neural cadherin-2 gene (CDH2) than dogs with a less severe phenotype (60 percent vs. 42 percent, respectively). That's compared to just 22 percent in unaffected dogs, the university reports in a prepared statement.

“This CDH2 gene is expressed in the hippocampus, a brain region suspected to be involved in obsessive-compulsive disorder,” Dr. Dodman says. “In addition, this gene oversees structures and processes that are possibly instrumental in propagating compulsive behaviors.”

Edward Ginns, MD, PhD, at the University of Massachusetts Medical School says the finding might lead to a better understanding of the biology of compulsive disorder and facilitate the use of genetic tests to screen for a propensity for obsessive-compulsive disorder in humans. “[It will enable] earlier interventions and even treatment or prevention of compulsive disorders in at-risk canines and humans,” he says.