Macon Magazine

What is that doggie in the window?

DNA testing can take guesswork out of your mutt’s history

by Kim Zachman

Tracy and Ron Davis wondered why their mutt Harley was so aggressive toward their bassett hound.

“We wanted to know if it was just male-on-male aggression or breed temperament,” Tracy Davis said. “We weren’t sure how to handle it.”

Besides being part beagle, it was hard to tell what else Harley was by his appearance. They decided to have his DNA analyzed with a new test called Wisdom Panel, developed by Mars Veterinary. The test required a blood sample drawn by their veterinarian, and the results were returned in three weeks.

When Harley’s test came back, the Davises were relieved to see that he had a significant amount of beagle, some bloodhound and a trace of pointer in his mix, all mild-mannered breeds. His fighting tendencies were obviously due to normal male-on-male aggression and should respond to training.

“We were very pleased with the results,” Davis said. “The only surprise was the bloodhound because we can’t see the physical characteristics, but he does have a very accurate sense of smell.”

Breeds carry certain temperament traits along with their physical traits. Hounds were bred for tracking and hunting, sheepdogs to herd and protect livestock and terriers as vermin exterminators. Each job requires a different set of behaviors and those behaviors are inherent in the genetic makeup of that breed.

“If the dog is not training well or has behavioral issues, knowing what breeds are in it can help in finding a solution,” said Jeff Brantley of Brantley & Jordan Animal Hospital.

Health issues can also be tied to certain breeds. Miniature schnauzers are prone to diabetes, German shepherds are more likely to suffer from gastric disorders and American cocker spaniels frequently develop glaucoma.

“It’s hard to readily identify breeds just by looking at the dog,” Angela Shurling of Riverside Animal Hospital said. “Knowing that a dog has cocker spaniel in it would help us plan its medical treatment. We would screen the dog for glaucoma during yearly physicals.”

Beware: Scientific Stuff

Although several companies now offer canine breed typing, Wisdom Panel has a relatively high level of sensitivity — it currently is able to identify 134 of the 157 breeds recognized by the American Kennel Club. Other companies, such as MetaMorphix, use a tissue swab instead of a blood sample and are able to type between 35-50 breeds.

In developing the test, Mars Veterinary collected over 13,000 samples of DNA from dogs in the United States and the United Kingdom. Using more than 300 DNA markers, scientists were able to build a library of distinct genetic signatures for AKC breeds, allowing the detection of those breeds in an animal’s genetic composition.

Even with the distinct genetic signatures, determining which breeds are present in a mixed-breed dog can be very difficult. Mutts vary in their complexity from a cross between two known parents to animals that intermingle freely in feral packs. It’s also easier to detect genetic signatures from the parents or grandparents than it is from great-great-great-grandparents. Wisdom Panel reports breed matches on a scale with “significant amount” being the strongest match to “trace amount” being the weakest. They don’t guarantee detection of all breeds in a mixed dog.

Complicating matters further, some of the newer AKC breeds were derived from older breeds. For example, the toy fox terrier was developed in the 1930s using fox terriers, Manchester terriers, Italian greyhounds and Chihuahuas to achieve the current standard that is recognized by the AKC. Would Wisdom Panel mistakenly report that a dog had Italian greyhound in its background instead of the toy fox terrier?

“It is possible that breeds that have been combined in crosses to ultimately form a new breed could potentially be detected as matches,” explained Neale Fretwell of Mars Veterinary. “If this occurs, this would most likely be reported as trace amounts of the ancestrally related breeds.”

Because of this overlapping of breeds, the genetic markers can be very similar and hard to differentiate. Wisdom Panel uses their proprietary computer algorithm to make the call between similar markers.

“The computer selects the single best combination of breeds and relative amounts of breeds detected that best match the tested DNA sample from this comparison with our extensive database of purebred AKC dog breeds signatures,” Fretwell said.

Back to Normal Now

It might be true that learning your mutt’s lineage could be an advantage in determining its health-care plan or its training regimen, but the main motivation for most pet owners is simple curiosity.

“People ask me what I think their dog is and I guess something, but really, my guess is as good as theirs,” Brantley said. “Sometimes I have no idea.”

Shurling agreed it’s hard to identify breeds in a dog just by looking at it. The Wisdom Panel results have been a source of amusement for her and her staff.

“It’s been interesting to us,” she said. “We all had our ideas about what breeds the dogs were and then the tests would come back and we’d be surprised.”

But curiosity could kill a wallet. The price of getting your dog tested with Wisdom Panel costs $150-$170, depending on the extra charges for the blood test and shipping. For some people that price is too high to find out if their suspicion is correct that Fifi is part French bulldog. However, for Thom Phillips, no amount of money was too much to discover his beloved PuppyLuppy’s genetic makeup.

“We thought that she was a mix of German shepherd and corgi, but we wanted to find out exactly what her breeds were so we could breed another one like her,” he explained. “When we got the results back, we realized that her personality is just a fluke of nature.”

PuppyLuppy, known as “Pup” to her family, came from a pack of wild dogs in North Carolina. The Phillipses found her outside their mountain home when she was barely 6 weeks old. When she was around 2 years old they started talking to her as if she were human and that’s when they realized her high intelligence.

“She responds much better to sentences,” Phillips said. “If you say, ‘Go, get the treat and bring it here,’ she’ll do it. If you say, ‘Get treat’, she’ll eat it.”

According to Wisdom Panel, PuppyLuppy is an extremely complex mixed breed dog, and her results are only found in 15 percent of the mongrels in the United States. There were trace amounts of five breeds detected and several more that were too weak to identify. Knowing that she came from a free-ranging, interbreeding pack of dogs, her convoluted lineage is to be expected. Replicating her would be a miracle.

“We accepted the reality of what is possible and what is not,” Phillips said. “We could find that personality in perhaps any breed or perhaps never again.”

Discovering what breeds our pound puppies possess can be valuable information, but most people would agree that it’s more fun than necessary. Just as Phillips discovered, our precious pooches are special, and we don’t need a test to learn that. M