Mans best friend helps disease hunt

For centuries man has had a uniquely close relationship with dogs. Now, dogs are taking on a new role - they are helping in the hunt for genetic mutations that lead to diseases in humans

Many canine diseases could share the same genetic basis in humans and dogs, and because dogs have been bred into clear isolated populations - the different breeds - it is often easier to detect a genetic flaw that leads to a disease than it is in humans. Once the rogue gene has been found in the dog, it could make it easier look for mutations in the same gene in man.

Speaking at the European Science Foundation’s Functional Genomics Conference, Kerstin Lindblad-Toh of Uppsala University in Sweden and the Broad Institute of MIT said: “Dogs get very similar diseases to humans. If you ask a dog owner what sort of conditions their pets get, they will say cancer, allergies, eye diseases.”

To examine this similarity a new European consortium - LUPA - has been set up, where twenty veterinary schools from 12 countries spread across Europe will work together to collect 10,000 DNA samples from purebred dogs, comparing healthy animals with those affected by similar diseases as human. The analysis of the genome of affected dogs compared to healthy ones of the same breed will lead to the identification of genes implied in the mechanisms of these diseases.

Functional genomics describes the way in which genes and their products - proteins - interact together in complex networks in living cells. If these interactions are abnormal, diseases can result.

“For example we have found genetic mutation that results in a condition called day blindness that can affect dachshunds,” Lindblad-Toh said. A similar condition can arise in humans, and analysis of the mutated protein in the dog is providing new information about the disease in man. The team is also looking at genes associated with cancer of the blood vessels to which golden retrievers are prone.