Dog DNA Testing Reliability (3 articles)

[ARTICLE #1]

DNA Testing Your Dog

DNA testing is a phrase that does not communicate very well because it means different things to different people. In dogs it can mean (1) determining the likelihood that specifically identified dogs are related, and perhaps how they are related (2) looking for the markers for a specific trait such as color or genetic condition such as PRA (3) attempting to discover what breeds are in a mixed breed dog. This last meaning has only come into being in the last couple years and is proving to be very popular, but is it accurate? That is the question asked here.

It appears that there is some way to go still on the level of accuracy for these tests. The sellers of these tests start with an advantage over their target client base. The target clients don't know the answer and so are in no position to refute the response provided. Some people, however, have submitted samples of dogs with known heritage and received results sufficient to question the accuracy of these tests.

One person produced a video of the process of submitting samples of her AKC registered American Staffordshire Terrier. The dog came back identified as Border Collie, Boston Terrier and Bulldog. The service used was BioPet Vet Labs DNA Breed Test. The site says "We believe that 92% of the mixed breed dog population in the USA is covered by our 58 validated breeds.".

Note that the American Staffordshire Terrier is not one of those 58 validated breeds. It is, perhaps, good news for those whose dogs are constantly faced with ill conceived breed specific legislation. However, while this test was inaccurate, failing to find the breeds typically covered in BSL, I think the point is well taken that it could just as easily be inaccurate in the other direction. Such a test might be used by authorities to "prove" that a particular dog is a mix of a restricted breed even when the dog's background contains none of that restricted breed. Genetic testing has already been used to successfully counter an official's opinion that a particular dog is of a mix subject to a breed ban. If these tests are proven to be unreliable then are we back to the often very inaccurate "expert" opinions of officials?

Another person reported the results of submitting samples for a Boston Terrier and a Keeshond. Canine Heritage identified the Boston Terrier as a mix of Cairn Terrier, Miniature Pinscher and Whippet. Canine Heritage states that they are able to successfully assign the correct breed over 99% of the time when testing purebred dogs on their breed list. Their breed list includes the Boston Terrier and so should have been able to identify it. DOG DNA identified the Keeshond as Golden Retriever, Akita, and Samoyed. They are, apparently, using the same test and breed list as Canine Heritage. (This was reported on a MySpace Group for Mix Breeds and Mutts "So I got my dna test kits this week. so excited").

The dna for one dog, Dakota, a dog of unknown heritage was submitted. The dog, a recessive yellow (ee) weighing 55 pounds, was identifed as 51% Boston terrier, 25% to 49% Basset hound, and less than 25% Bulldog. The dog owner recognized that this was extremely unlikely and contacted the lab. The lab admitted an error had been made but has not yet sent the replacemen results. The dogs pictured in an article published in the Houghton Lake Resorter also seem unlikely to have the breed inherirtance reported. An article by Linda Dahlstrom on MSNBC similarly questioned the results ... or rather lack of results but concedes that the problem might have been the very limited number of breeds identifiable at that time (38). The comments following the article provide additional consideration. I'm somewhat puzzled by the number of reports that include field spaniel, usually in trace amounts. The breed is very rare.

Deteriming that the test results on an unknown mixed breed are blatently incorrect is challenging but can be done by someone sufficiently familiar with typical inheritance patterns. While there are plenty of happy customers and properly identified purebreds and mixed breeds the number of reports of unlikely mixes suggests there is some development yet to go before there is a reasonable level of reliability.

[reposted from: http://www.dogplay.com/GettingDog/dna_testing.html ]

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[ARTICLE #2]

Unraveling the Mutt Mystery | 2009-09-22

Understanding DNA Testing Options for Dogs

It's hard to imagine that the fuzzy monster who tracked mud through the kitchen might actually hail from a long line of purebred perfection. But we're here to tell you it's entirely possible. Thanks to a handful of new DNA testing programs, you may even be able to prove it, or at the least learn what breeds dominate your dog's family tree. Dog people across the country are plunking down up to $125 a pop to finally get definitive answers to the one question they hear everyday at the dog park – "cute dog, what kind is it?"

As if curiosity wasn't enough, some folks spring for the tests to help explain canine behaviors such as rooting around after moles (Terrier?) or even a propensity for congenital conditions such as hip dysplasia (German Shepherd?). But with up to four competing DNA companies who promise to analyze doggie cheek cell swabs or blood samples, the Woof Report wondered, how do you choose which test is most accurate? That's where the The Wall Street Journal comes in.

Paula Szuchman, the author of last week's WSJ article on this topic had her pup's DNA tested with four popular dog DNA services: BioPet's DNA Breed Identification, MetaMorphix's Canine Heritage Breed Test, Mars Veterinary's Wisdom Panel MX Mixed Breed Analysis and DDC Veterinary's Dog DNA Breed Analysis. The results? All four services offered different results. To view Szuchman's full article and see her helpful chart on how the tests compare, see the link below. In the meantime, here are the highlights from Szuchman's experience:

DNA Is So Random. Canine genetics is a new field of scientific study. Isolating specific genetic breed markers such as ones for body type requires samples from purebred dogs. If the breed is more common, hundreds of samples can be collected versus just a few for less common breeds. This can present limits on DNA testing. In fact, Szuchman notes that the Mars testing company database featured information for up to 157 breeds over DDC's meager 63. That said, check the breed list before you choose a company to see that it includes the breeds you suspect your pup to be.

Looks Can Be Deceiving. Szuchman also found that some of the results did not match up to her dog's appearance. One company explained away this concern stating that because dogs receive DNA randomly from both parents, they present differently in each dog. This variation is what makes every dog unique, a concept that was also confirmed by animal geneticists.

You can take the dog out of Europe, but you can't take…Distant doggie relatives of the same breed share similar DNA, but the code can vary from country to country. With up 400 dog breeds around the world, and only about 160 recognized in the US, it's simply not possible to analyze each breed for its unique genetics.

The Scoop:

Read the full article from Paula Szuchman in the The Wall Street Journal, "Beagle or Bichon: Can Dog Drool Provide Insight?"
www.online/wsj.com/dogdna — reposted BELOW:

[reposted from: http://www.woofreport.com/archive/index_tip.php?id_story=341 ]

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[ARTICLE #3]

Beagle or Bichon: Can Dog Drool Provide Insight?

By PAULA SZUCHMAN

Advances in DNA testing have changed the way we pursue criminals, verify paternity and date medieval manuscripts. Now it's being used to answer one of the greatest riddles mankind has ever faced: What kind of dog is that?

A new pack of genetics companies say they can tell mutt owners which breeds their dogs come from, for a fee of $60 to $125. The results, say the companies, can satisfy simple curiosity, provide clues to a dog's behavioral quirks, and even help identify breed-specific health problems.

But can a few strands of DNA really hold the answer to your dog's inner being?

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Yaniv Nord

What kind of dog is that? Parrot, who may be made up of Italian greyhound terrier, Boston terrier, bichon frise, golden retriever, mastiff, West Highland white terrier, Staffordshire terrier and/or bull terrier, according to various dog-DNA tests, plays in a Brooklyn, N.Y., park.

To find out, we subjected our lovable, squeezable and all too agreeable mutt named Parrot to DNA tests offered by four companies. He happily sat still while we swabbed the inside of his cheek, and he didn't bristle when we took him for a blood draw at the veterinarian for one of the tests. In the end, he learned nothing (except maybe that swabs equal treats), but we learned that the business of dog DNA isn't as simple as it appears—starting with the fact that all four labs came back with different results.

The first lab we tried was DDC Veterinary in Fairfield, Ohio. The parent company has long focused on human DNA testing, mostly performing paternity tests, including, says the company, the one for Anna Nicole Smith's daughter. With that pedigree, we expected DDC to give us solid proof of Parrot's lineage, too.

The online buying process was easy. We paid $68 and received our swab kit in a few days. We sent the swabs back in the self-addressed, stamped envelope provided, and in a couple weeks, got our results. An official-looking certificate with a gold seal listed six breeds, grouped by the level of strength of each, on a scale of one to five: Italian greyhound and Boston terrier (level three); bichon frise and golden retriever (level four); mastiff and West Highland white terrier (level five). Also included was a list of each breed's behavioral traits and common health problems, and an explanation of what the levels mean. A level one, for example, indicated that the breed contributed to more than 75% of the dog's DNA, down to less than 10% for a level five.

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none needed

It all made sense, except for one thing: Parrot looks like none of those breeds. What he looks like is a pit bull, mixed with who-knows-what. At the shelter where we adopted him, he was listed as part pit bull, part weimaraner. Others have said he resembles a pointer or a Labrador retriever. He weighs 65 pounds, and measures more than two feet tall and three-and-a-half feet long. He's a big dude.

Bichon frises look like little white puff balls. Italian greyhounds are small and spindly.

In its material, DDC has the caveat: "DNA is inherited randomly from each parent which makes every dog unique. This is why a dog's appearance may look different than the breeds detected in the DNA test."

This is true, according to animal geneticists we spoke with. But the plot thickened when we got the results from Mars Veterinary's Wisdom Panel DNA test. A division of candy and pet-food giant Mars Inc., Mars Vet goes a step further than its rivals by requiring a blood sample, which meant paying our vet $20 to draw blood. The test was already the most expensive in the bunch, at $124.99. The company says blood has more DNA on it than a cluster of cheek cells.

All the companies we used, including Mars, had easy-to-navigate Web sites. In each case, our kits arrived within days, complete with self-addressed stamped return packages and clear instructions. All sent the results back two to three weeks later. In the case of Mars, our vet offered to pop the return envelope in the mail.

But what differentiates Mars, as we came to learn, is the number of breeds in its database: 157. In contrast, DDC has 63. Among the breeds Mars has that DDC and others don't is the American Staffordshire terrier, also known by some dog experts as the American pit bull terrier—the dog we thought Parrot most resembled. Mars's test showed that at least 25% of Parrot's DNA came from the Staffordshire terrier, meaning one of his grandparents might have been a purebred. At least 12.5% came from the bull terrier, which comes from the same ancestral group, and a trace came from the wire fox terrier. None of the breeds detected by DDC were found.

And therein lies the limits of dog DNA testing. Still a relatively new field, canine genetics is an inexact science. To locate the genetic markers that might differentiate a breed—markers that control for size, for example -- companies take samples from purebreds with established pedigrees. Depending on how common the breed, they might sample anywhere from a handful of dogs to hundreds. Mars's chief geneticist, Neale Fretwell, estimates it costs a minimum of $20,000 to get a new breed into the database.

But geneticists say the DNA of dogs even within a given breed can vary widely depending on the country they are from. In addition, breeds within the same group -- such as terrier -- can be very similar genetically. Also, a single dog has billions of bases, building blocks of the genome, and these DNA labs only look at a few hundred. What's more, there are thought to be as many as 400 dog breeds world-wide -- roughly 160 of which are recognized by the American Kennel Club -- and it would be impossible to know for sure that a breed has a unique genetic sequence unless every one of the breeds was analyzed.

Breeds that show up as contributing to a large part of your dog's DNA are likely to "accurately reflect a dog's composition," says Urs Giger, a clinical geneticist at the University of Pennsylvania School of Veterinary Medicine. But of the breeds that come back in amounts of less than 10%, he says, "you can't be sure" that your dog's makeup actually contains that breed.

Mars's Mr. Fretwell says the company samples dogs from around the world and is constantly updating its database. He says extensive tests were done to find the markers that would most reliably predict a dog's breed: "We haven't yet found a breed that's indistinguishable from another breed."

Randy Smith, account manager at DDC Vet, says the list of breeds it screens for includes the most-common ones, but adds dog owners should check the list before buying the service, in case the breeds they suspect their dog has isn't on it.

DDC doesn't do the tests at its lab. It works with BioPet Vet Lab, of Knoxville, Tenn. We also got a kit directly from BioPet, for $59.95, which came back with virtually the same results, leaving out only mastiff. When we called BioPet to ask about the discrepancy with DDC and the other companies, we spoke with Meg Retinger, the company's chief administrative officer. Ms. Retinger said the 63 breeds in its database cover about 92% of the DNA present in mixed-breed dogs in the U.S. "Our objective was to provide good coverage at a reasonable price," she said.

When the lab scanned Parrot's DNA, said Ms. Retinger, no one breed emerged as dominant, so the software looked for the closest matches. The fact that it came back with Boston terrier was telling, she said, since that breed is in the same family as the American Staffordshire terrier, which is not in the database. She said the lab is working hard to add the Amstaff and is collecting samples from breeders. Customers can request that their dog's DNA be retested free of charge whenever the lab adds a new breed. Customers can check the company's Web site for breed updates.

Our final test was conducted by MetaMorphix, a biotech firm that does genetic testing of livestock and parentage testing for the AKC. Its Canine Heritage Breed Test is built on 10,000 samples from 108 breeds. "Waiting for your dog's DNA test results can rival the anticipation of a new baby," according to the Web site, from which we purchased our kit for $99.95.

Here again, our results were different: Staffordshire bull terrier was ranked as "secondary," meaning it has a "strong influence" on our dog, but "makes up less than the majority" of his DNA. The breed is related to the Amstaff, which MetaMorphix doesn't have in its database, so at least we knew it was a likely contributor to Parrot's DNA. What the company does offer, though, is a certificate that comes with a photo of our cutie pie, which we're now proudly displaying on our cubicle wall.

Still, nearly $400 later, when people on the street pass us and ask what kind of dog Parrot is, our answer hasn't changed: "Who knows?"

COMPANY	TEST	PRICE	COMMENT
BioPet Vet Lab Biopetvetlab.com (866) 883-7389	DNA Breed Identification	$59.95	Launched 18 months ago, the test can detect 63 breeds, which the company says covers about 92% of U.S. mixed-breed dogs. New "PooPrints" program identifies dogs by their droppings to encourage people to pick up after their pooches.
MetaMorphix Canineheritage.com (800) 362-3644	Canine Heritage Breed Test	$99.95	Company says it doesn't include American Staffordshire terrier or pit bull terrier in its database because the breed is a hot-button issue in some municipalities.
Mars Veterinary Wisdompanel.com (888) 597-3883	Wisdom Panel MX Mixed Breed Analysis	$124.99 + price of blood draw at the vet	Web site is among the most informative of the bunch, with a detailed FAQ, and we liked that results were sent both via email and regular mail. This month, Mars will launch a less-expensive, cheek-swab version of the test and the blood version will be available only through vets.
DDC Veterinary Vetdnacenter.com (800) 625-0874	Dog DNA Breed Analysis	$68	Resells BioPet's test, which includes a list of breeds' common health problems. Experts say not to jump to conclusions, though, since the canine ailments may not be present if your dog has only a small amount of a given breed's DNA.