Are dog DNA tests accurate?

From canine clothing to pet resorts for Rover, many dog owners shell out big bucks for puppy perks, treating their four-legged friends like family. The latest trend is DNA testing for dogs. The tests claim to reveal your dog's breed or breeds if you have a mutt. It's information that they say can be useful because some breeds are predisposed to certain medical conditions. Channel 2 wanted to see just how accurate the DNA tests are.

Brutus, 8, is a talker and tail wagger -- and he was a real trooper when his human, Channel 2 producer Lauren Brown, had to take cheek swabs for DNA testing. We purchased the two most popular canine DNA tests available. DNA My Dog cost us $68.97. We paid $69.99 for Wisdom Panel. The companies send you kits with swabs and instructions of how to collect the samples. You mail them back and wait four to six weeks for results.

Pup parents Lauren and Tyler sat down for a breed reveal when the results came in. DNA My Dog, which requests a picture of your pooch along with the cheek swabs, reported Brutus is a mix between an Italian Greyhound, a Catahoula Leopard Dog and a Great Dane.

"I did not see any of those coming," Tyler said.

Wisdom Panel reported completely different results. It showed Brutus is a 50-50 mix of a Rat Terrier and a Russell Terrier.

"What are we supposed to conclude from that?" consumer expert Amy Davis asked Meyerland Animal Clinic veterinarian Sarah Pella.

"A lot of it, it's just out of curiosity or for entertainment value at this point," Pella said.

Pella said the tests collect just a tiny bit of DNA called a snip. It can go several generations back. Depending on what section the testers grab, results could vary greatly.

"It can certainly be frustrating," said Pella.

"And I think there's just still a lot of research going on."

When we contacted both companies, DNA My Dog offered to do a second test with new swabs from Brutus. Those results revealed he is Italian Greyhound, Rat Terrier and Catahoula Leopard dog. A DNA My Dog representative said the Great Dane result was likely due to some sort of contamination of the sample we sent in.

Wisdom Panel told Channel 2 it screens for more than 250 breeds. DNA My Dog told us it screens for 88 breeds. Pella said tests screening for more breeds usually will lead to more accurate results.

Below are the full statements from both companies:

DNA My Dog:
"As it states on our order form any contamination will affect results. In all but a very few cases we are able to catch it. The test is only as good as the sample and any home based DNA test is subject to the same potential for bacteria and contamination. Especially when it comes to dogs who have high levels of oral bacteria.
In our experience, even when it comes to the average consumer. as you call it, people aren't so average when it comes to their dogs! If we provide results that don't make sense to one of our clients they will absolutely be in touch
In most cases it is just a matter of explaining the results to them but if something looks "off" we will examine the lab report to see if we can spot anything, we will retest as necessary. I would say in the majority of cases the retests come back the same. Of course for you, since it is a news story, it didn't! But we do retest for anyone who looks like they need a new test
We test for 88 breeds representing the most common breeds in the mixed breed population. We limit the breeds to keep the price down, ensure a high level of accuracy and a quick turnaround. We add breeds based on demand and popularity of certain breeds."

Wisdom Panel:

"There are really three important components to analyzing DNA for breed ancestry:

1.The number of dog breeds represented in your panel - While many breeds share the same traits, to get a truly accurate reading the more breed signatures you have to work from the more refined you can get.

2.The number of markers along the genome that you are looking at - these marker locations are chosen specifically for breed and the more you have the better your analysis.

3.Technology, or the algorithm taking this information and doing the final assigning of the breeds.
Mars Veterinary, makers of the Wisdom Panel® Canine DNA Tests has been in the field of canine genetics for nearly a decade and we hold the exclusive, worldwide license for the genetic breed detection process pioneered by renowned canine geneticist Dr. Elaine Ostrander during her time at the Fred Hutchinson Cancer Research Institute.

The Wisdom Panel test screens for 250+ breeds, types and varieties, along 1800 markers, and uses a robust algorithm that performs more than 18,000,000 calculations before assigning 11 possible family trees and refining from there to the final one you see.

I had a veterinary geneticist from our team review your results just to be sure and she said without a doubt it was a 50/50 mix of Rat Terrier and Russel Terrier."