Is DNA testing in dogs a sham?

There is an article in the Toronto Star, by Nancy J. White, about a woman who sent her dog's DNA sample to three separate companies for testing. The results were, well inconclusive to say the very least. 


This reinforces what I have been saying all along about breed identification? 


Here is a picture of the dog.

DNA tests confirm we have a mutt

Companies agree there's shepherd in Whiskey

All we knew for sure was that Whiskey was a lovable, furry mutt.

Three DNA tests and $268 later, all we know for sure is that Whiskey is a lovable, furry mutt.

The results from three companies agreed only on this: our boy is one mixed-up canine cocktail and he does have some shepherd. But what kind of shepherd and what other bevy of breeds make up the mix is up for grabs.

Suggestions ran the genetic gamut from the small Norwich terrier to the enormous St. Bernard, with a bit of beagle, a dollop of Dalmatian and some Rottweiler, among others, tossed in.

He looks like none of those.

"You can't judge a dog by his cover," explains Robin Ray, marketing director for the Canine Heritage Breed test.

The revolution in DNA testing has gone to the dogs. Geneticists have mapped the genome of the domesticated dog and researchers are studying genetic influences for diseases that afflict canines as well as insight into those shared with humans, such as cancer and diabetes.

And just as DNA samples are used to trace humans' genetic ancestry, so too Rover's.

"The majority of the dogs we test come from shelters and owners are super curious," says Mindy Tenenbaum, of the Toronto company DNA My Dog. "Ninety per cent of the time people are wrong about what they think the dog is."

The companies say that knowing the breed can shed light on a mutt's potential health problems.

Tenenbaum tells the story of a large dog resembling a king shepherd with a bad skin affliction that the veterinarian couldn't cure. The owner happened to mention that DNA results showed the dog was part Siberian husky. The vet knew that huskies often get a certain type of dermatitis and successfully treated the animal.

We weren't curious so much about Whiskey's health or even his lineage as we were the tests. Crucial to the test is a company's database: How many breeds and which ones will they compare to your pet's DNA? There are about 500 breeds of domesticated dog.

The three tests we ordered, all available online, ranged in price from $70 to $108, and promised 90 per cent or better accuracy. The three companies say their DNA databases come from certified American Kennel Club dogs or, in cases of breeds not part of AKC, from top-notch breeders.

The kits arrived with instructions and swabs to collect cells from inside the dog's cheek. Whiskey barely noticed. I mailed back the DNA-swathed swabs and waited a few weeks for results.

When my family adopted Whiskey more than 10 years ago from the Toronto Humane Society, we were told he was a stray, most likely a shepherd-collie mix. That was their best guess and fine by us.

DNA My Dog, which tests for 68 popular breeds, found that Whisk was a level three Australian Shepherd, meaning he likely had a grandparent predominantly from that breed. On the great-grandparent level, there was a lot of bizarre mating going way back: Shetland sheepdog, Siberian husky, beagle, golden retriever and St. Bernard.

"Holy cow, that is a lot," says Tenenbaum when told of the findings.

A Google search of Australian shepherd shows a black and tan, hairy dog that sure looks like Whisk.

The breed is known for its intelligence, herding and guarding instincts. Sounds like Whisk. He used to nip at our heels and try to herd us together. And did I mention he was tops in his puppy obedience class?

On to company number two, the U.S.-based Wisdom Panel Insights, which tests for more than 170 breeds, the most in our three-way sample. It registered zip in the significant or intermediate categories but detected minor signs of German shepherd and traces of bearded collie and Rottweiler.

I felt confused, so I emailed Wisdon Panelstaff veterinarian and geneticist Angela Hughes a picture of my long-haired, flop-eared sweetheart who looks nothing like a German shepherd.

"I disagree," says Hughes who singled out Whisk's German shepherdy traits, such as the tan base coat and black overlay. German shepherds come in a long-coated version, she says. Both bearded collies and Rottweilers have dropped ears like Whisk. His broad skull could be rottie.

Looking at his hybrid results, she says: "I'd expect him to be a very intelligent boy." Why, yes.

The third one, Canine Heritage, tests for 106 breeds. It also drew a blank for any primary matches, but on a secondary level: Dalmatian.

Dalmatian?

"It's at the bottom of the threshold," explains marketing director Ray, calling up Whiskey's results. The spotted breed, made famous by Disney, ranked just a tad above the "In the Mix" findings: German shepherd, Australian shepherd, Norwich terrier and St. Bernard.

"Looking at the findings," says Ray, who never saw Whisk's photo, "I'd guess you have a generic black dog with a white chest spot."

Close enough. That's apparently a common look among the Heinz 57 set. Black is a dominant trait.

So whom to believe?

At the Ontario Veterinary College in Guelph, staff veterinarian Rasa Levstein says a good test must be reproducible and suggests doing all three again. No time for that.

For health purposes, she says it may be useful to know the mutt's breeds, but only if the test is accurate. Otherwise, she warns, an owner would be "barking up the wrong tree."

At the Rosedale Animal Hospital, veterinarian Ian Sandler calls the tests a good option for the curious. but not of much help clinically. Dogs have similar disease patterns depending whether they are small, medium, large or extra-large.

"Knowing specifically whether it's mostly German shepherd or golden retriever wouldn't play a huge role in how the dog is treated," he explains. "It's more of a novelty at this point. In the future, as technology improves, it may help identify the potential for various diseases."

As for Whisk, he remains our noble beast, nary a drop of blueblood in him. But his new nickname is "Aussie."