Misidentification can lead to breed stigmas

By Dr. Beth Leermakers

Does it really matter what breeds make up your mixed breed dog? While having the right “designer” breed mix (think Labradoodle or Golden Doodle) is very important to some people, there may be important health reasons for knowing your dog’s ancestry. There are several reasons to consider DNA testing for your dog, whether she’s purebred or a mutt. 

Breed Identification

If you adopted your dog from a shelter or rescue group, without knowing who their parents were, you may be curious about Fido’s breed mix. Your dog’s breed make-up may indicate an increased likelihood of particular health conditions developing in the future.

Genetic Health Risk Identification

Once used primarily to identify breeds, some DNA tests now also pinpoint the risk for genetic health conditions by identifying genetic mutations that cause disease. Some genetic mutations are common in certain breeds. For example, herding breeds, like collies and shepherds, often carry a defect in the multi-drug resistance gene, MDR1, which leads to an increased risk of severe, life-threatening adverse reactions to some commonly prescribed medications such as Ivermectin (used for heartworm prevention). 

The Embark Breed Identification and Health Condition Identification DNA Test in Dogs provides a genetic health screen for more than 230 medical conditions in 16 areas of the body, including drug sensitivities, degenerative diseases and bleeding tendencies. By knowing in advance that your dog may develop hip dysplasia or cataracts, you can take steps to prevent or manage these conditions. 

Veterinarians caution people that DNA testing has limitations. Scientists have been gathering information about which genes are associated with which conditions, but the research is in its infancy. Correlation does not mean causation; a gene that often occurs with a particular disease might not cause it.

DNA Tests May Help Shelter Dogs Get Adopted 

Pit bulls and chihuahuas are two of the most common breeds that wind up in animal shelters. Adopters tend to overlook pit bulls because of their reputation (often incorrect) for being aggressive. 

Or pit bulls may be banned by people’s apartment or home owner’s association. Correctly identifying dogs’ breed mix may help the pitbull-looking dogs find forever homes. 

People tend to call any short-haired muscular dog with a blocky head a “pit bull.” Determining a dog’s breed based on visual inspection alone is difficult, even for experts. One study asked dog experts to examine photographs and guess the dogs’ breed. The researchers compared the visual assessments to DNA test results. The “experts” correctly identified 14 dogs as having some pit bull (American Staffordshire Terrier or Staffordshire Bull Terrier) in them. However, they incorrectly labeled 17 dogs as pit bull mixes when DNA testing revealed a complete absence of pit bull heritage.  

I witnessed this misidentification first-hand when I participated in a DNA test fundraiser for a rescue group. At the reveal party (when we received our dogs’ test results), the organizers shared the results of several dogs who attended the party. A few dogs, who appeared to be pit bulls, didn’t have any pit bull in their mix. Other dogs, including a little fluffy white dog, had a small amount of pit bull. My dog, who looked like a Rottweiler mix (with brown spots over his eyes and on his bottom), didn’t have any Rotti in his lineage.   

In California, 25 percent of the shelter dogs appear to be chihuahuas. These dogs often look alike, so they don’t stand out to adopters who are looking for a more distinctive pet. In an effort to find homes for chihuahuas, Bay Area’s Peninsula Humane Society DNA tested 12 dogs that appeared to be chihuahuas. After discovering the unique mixed backgrounds of these dogs (such as a Chihuahua Corgi mix) and advertising them as such (a “Chorgi”), the animals were all adopted within two weeks — twice as fast compared to similar-looking dogs with uncertain backgrounds.

What are the Best 

Dog DNA Tests? 

Embark. The Embark dog DNA test is one of the most popular dog DNA test kit brands. Developed with the Cornell University College of Veterinary Medicine, the Embark Breed and Health kit screens for more than 350 dog breeds, making it one of the most accurate tests on the market, and more than 200 genetic health diseases. The test costs $139 and takes about two to four weeks to get results. 

Wisdom Panel. Wisdom Panel has tested more than 3 million pets. Their breed identification is often the most accurate because they have the world’s largest database of breeds. Their Premium Breed Identification and Health Condition Identification DNA Test for Dogs tests for more than 210 genetic health conditions. The test costs $160. 

If you’re curious about your dog’s breed mix or health risks, look for discounts on the DNA test kits. 

DNA testing may tell you something that helps you keep your dog healthier. If nothing else, you’ll have something fun to share at the dog park.