More and more pet owners are testing their canine’s chromosomes
Rick Woods’ dog, Stanley, is a lanky, lumbering mutt with the head of a black Labrador retriever and the body of a German shepherd. So Woods was a little shocked when results from a doggie DNA test said Stanley was a mix of black Lab and American Eskimo dog — the latter a white, fluffy breed that spins in circles when it gets hyper.
“It looks nothing like Stanley,” says Woods, a Colchester resident who bought the home DNA kit for $75 at Petco in Burlington.
Woods called the testing company, Tennessee-based BioPet Vet Lab, to see if there was some mistake. He learned that the lab compared Stanley’s cheek swab against 64 known breeds in its database — a sample that captures some 95 percent of mixed breeds in the U.S. But when the analysis doesn’t get an exact hit — as happened with Stanley, Woods found out — it jumps to the next most similar DNA. In Stanley’s case, that was American Eskimo dog.
With BioPet’s help, Woods deduced that Stanley’s actual breed was probably Lab mixed with Chinook, a less common breed of “sled dog” related to the American Eskimo dog.
But the mystery went deeper. Woods also learned that Stanley has trace amounts — often less than half a percent — of dozens of different breeds, from the 6-pound Chihuahua to the 180-pound St. Bernard. The lab techs explained that such genetic “noise” — trace amounts of many breeds — is typical, because all dogs are descended from common wild ancestors.
It’s enough to give a pooch, and his owner, an identity crisis.
As cheap pet DNA test kits have proliferated in recent years, an increasing number of dog owners are shelling out money — usually $60 to $100 — to find out what breeds their mutts mix. Some do it out of curiosity, others to learn about behavioral or health problems — such as epilepsy or hip dysplasia — to which a dog might be predisposed. And, as Woods learned, the results can be as baffling as they are enlightening.
So, what do you get for $100? Most canine chromosome kits come with a sterile DNA collection swab to scrape skin from inside the dog’s cheek and a protective sleeve in which to mail the sample back to the lab. Results are usually mailed or emailed within a few weeks and give a family history — sometimes going back four generations — along with details about the traits and features of those breeds. One of the larger canine genetics companies, California-based MMI Genomics, claims it has sequenced more than 500,000 dog DNA samples and is the principal service provider for the American Kennel Club and United Kennel Club.
But dog DNA testing isn’t just a novelty for curious pet owners. It’s increasingly being used for serious things — such as crime fighting. Call it “CSI: My Doggie.”
In Wisconsin, the case against accused murderer Michael Haydon was stalled for lack of evidence until dog hairs found at the crime scene proved a match to the suspect’s German shepherd, Boomer. Indiana prosecutors were reportedly able to convict a man of murder after dog poop on his sneaker tied him to the scene of the crime.
The University of California, Davis, maintains a criminal dog-fighting DNA database, the nation’s first, established by a consortium of animal-welfare groups, including the American Society for the Prevention of Cruelty to Animals and the Humane Society of Missouri. Known as the Canine CODIS (Combined DNA Index System), the database was launched to help law enforcement investigate and prosecute dog-fighting cases by using genetic samples to link breeders, trainers and dog-fight operators.
Some even want to use canine DNA to fight dog doo. In a 2005 New York Times column, Freakonomics authors Stephen J. Dubner and Steven D. Levitt called for mandatory dog DNA collection as a way to identify the canines pooping on New York City sidewalks and punish their owners for not scooping.
Three years later, the mayor of Petah Tikva, Israel, did just that, and is credited with developing what the Times called “the first-ever forensic dog-poop DNA unit.” In the U.S., a ritzy condo complex in Baltimore made national news last year when its board proposed mandatory DNA swabs for all resident pooches and $500 fines for owners who don’t pick up after them.
Here in Vermont, the kits sell in pet stores all over, including Pet Food Warehouse in South Burlington and Shelburne, where Cindy Eaton works in accounting. Eaton bought a DNA kit to test her mixed breed, Dixon, both out of curiosity and so she could better understand how to deal with his behavior. Dixon was a street dog in Puerto Rico when Eaton adopted him last year, and though he’s mellow and friendly, she says he’s prone to wandering.
So, Eaton swabbed Dixon’s cheek using the Wisdom Panel Insights kit, a $70 product manufactured by Maryland-based Mars Veterinary, and mailed it away. In three weeks, results came back showing Dixon was a true mutt: Labrador retriever mix on one side, and cocker spaniel and Alaskan malamute on the other.
“In a million years, I never would have thought cocker spaniel when you see my dog,” says Eaton. “But when you read through the breed and some of the trait characteristics, it is believable.”
The breed report even made Eaton see traits she had overlooked before: Dixon’s bushy tail is textbook Malamute, and he has cocker spaniel “feathers” on his ears and back. His ears flop like a Lab’s.
“It was right on,” Eaton says.
Gina Berk of Charlotte had a very different reaction to DNA results for two mixed-breed dogs she adopted from the Humane Society of Chittenden County, where she is a longtime volunteer and former board president. She found the whole thing implausible.
To Berk, Clyde and Nelle looked like golden-retriever mixes with their long, bronze coats, but she wanted to be sure. Also, Nelle is epileptic, and Berk wondered whether breed was contributing to her health problem. So she swabbed their cheeks and mailed the samples to Mars Veterinary.
“When we got the reports back, I took it to the vet to show him, and I thought he would drop dead laughing,” Berk says. “He was hysterical. He said, ‘That’s absolutely the stupidest thing I’ve ever seen as far as results go. That’s absolutely impossible.’”
It said Nelle was a golden retriever mixed with beagle — conceivable, given the pattern of white on her snout, chest and paws. But Clyde’s results were utterly baffling to Berk. The report said the shaggy mutt was a blend of Chinese crested — a nearly hairless dog with bushy tufts on its head, paws and tail — plus collie and Kerry blue terrier. Berk found the results “ridiculous,” noting the company’s generic breed descriptions such as “responds well to reward-based training.”
“Most dogs are food motivated,” Berk observes. “If I didn’t work at the Humane Society, I might be more gullible.”
University of Vermont biology professor C. William Kilpatrick has studied animal genetics and DNA sequencing and says it’s common for mutts to look nothing like their parents or grandparents. The reason why is most easily seen in parts of the world where feral dogs start interbreeding and, after a while, all begin resembling one another. After just two or three generations of such breeding, traits tend to get intermingled and lost, Kilpatrick explains. Recessive genes explain how two mixed-breed dogs with white or yellow coats could produce a black puppy.
An outgrowth of the Human Genome Project, dog DNA identification is only a few years old, Kilpatrick says, and the technology is bound to improve as testing labs expand their sample sizes.
“These things are only as good as the database. That’s where the weakness is,” Kilpatrick says. “Sometimes the mix is going to be well represented in the database, and they should be able to identify it readily. Other times they might not get a real strong signal.”