DNA Testing Facts

Hello, everybody!

Why is it important to learn the facts about DNA testing? 

Well when you educate yourself on this topic, you will be able to accurately understand test results and decipher between what should and shouldn't be concerning about the companies analysis. 

Why Is DNA Testing So Important?

If you have a purebred dog, you don’t need a DNA test to learn their ancestry. However, DNA testing can still pinpoint their risk for some genetic health conditions. 

Health is the most important thing, therefore reputable breeders will test for inherited problems known to occur in a breed and share that information with you. For example, veterinarians now recommend MDR 1 testing for any herding breed and some sighthounds. That gene regulates sensitivity to certain drugs, which can be important in an emergency.

Plus, any dog who is going to be bred should be tested for inherited problems known in their breed. “Breeders have long known the importance of genetic screening to avoid producing puppies affected with known genetic conditions. For individuals with pedigreed dogs, genetic health screening is crucial to ensure you’ve added a healthy, well-bred dog to your home.”

 Additionally, the DNA sample may be used for research to study ways to advance the prevention, detection, progression, and treatment of serious canine health conditions that in turn help future generations of dogs.

Understanding Results

Clear

If the dog's result is "clear", it means that the dog is not a carrier of a health condition nor is it at risk for developing any clinical diseases or conditions.

Carrier / Notable

If the dog's result is "Carrier or Notable ", it means that the dog carries one copy of a health condition. This result will not impact or affect the dog's health in any way. It means the dog carries this variant and will pass the carrying status on to ~50% of its offspring.  If a dog has a carrier status the dog is perfectly healthy to keep breeding as long as the dog is never bred to another carrier of that same disease or condition.

Affected, Positive, Increased Risk

If the dog's result is "Affected, Positive or At Increased Risk", it usually means that the dog carries two copies of a health condition. This result will most times mean the dog is likely to be affected by a health problem. Since the dog has two copies of the condition it means that this dog has a high chance of passing it down to their puppies every time. This means this dog should not be bred. This result is not the case for "Linkage or Provisional" tests.

What Do The Top 4 Dog DNA Companies Recommend Chinese Cresteds Be Tested For?

Between Embark, Wisdom Panel, Animal Genetics & Gen-Sol they recommend 12 tests in total even tho some are not even known to occur in our breed. 

Known To Our Breed

CMSD - Canine Multiple System Degeneration

DM - Degenerative Myelopathy

HUU - Hyperuricosuria

NCL7 - Neuronal Ceroid Lipofuscinosis 7

PLL - Primary Lens Luxation

PRA - Progressive Retinal Atrophy

PRCD - Progressive Rod Cone Degeneration

PRCD3 - Progressive Rod Cone Degeneration

VWD2 - Von Willebrand Disease Type II

Not Known To Our Breed

CDDY -Chondrodystrophy "Short-Legged Breeds" (Dachshunds, Corgi's) This Test Is A Linkage & Provisional Test

CDPA - Ostio-Chondrodysplasia "Short-Legged Breeds" (Dachshunds, Corgi's also found in Miniature Poodles)

IVDD - Intervertebral Disk Disease "This Test Is A Linkage & Provisional Test"

Should You Be Worried About Provisional Or Linkage Test Results Being At Increased Risk?

A text box with the words " intervertebral disc disease ( type i ) chondrodystrophy and intervertebral disk disease, c

No, you shouldn't, and this is why.

What is a Linkage Test?

DNA sequences that are close together on a chromosome tend to be inherited together. Because of this, they can use genetic variation surrounding a specific variant (i.e. "linked" to it) to infer the presence or absence of a variant that is associated with a health condition or trait.

Butt.... Embark states that
Linkage tests are not as predictive of your dog's true genotype as direct assays, which they use on most "other genetic conditions" they test for....

What Are Provisional Results?

Embark states that they use a high-density, high-accuracy genotyping platform with single-probe reproducibility of 99.9% with >99% call rates. Their "standard" health tests have been validated using a known carrier and affected samples to ensure design accuracy and use multiple probes to ensure highly accurate results (essentially 100%).

Butt..... Embark states that

Provisional tests are for rare disorders for which
DNA from carrier and affected individuals are not available for calculating test reliability, or for structural variants where more testing is needed to ensure the same level of accuracy.

They also ask that if you are a researcher or breeder with access to
DNA from a carrier or affected individual and are interested in helping them validate tests, to please contact them at research@embarkvet.com.

It clearly states that it's not reliable or accurate. Below I Have Posted Pictures Directly From There Website To Show You.

A text box with an image of a dog.
A text box with an image of a dog.

Will a DNA Breed Identification Test Prove My Dog Is Purbred? Absolutely Not!!

Contrary to what DNA companies say about the accuracy of their breed verification testing, this is without a doubt not as precise as they lead you on to be. As I stated previously, if you have a purebred dog, you don’t need a DNA test to learn its ancestry or prove if it's indeed a purebred. Currently, there is no DNA company that guarantees their breed testing is 100% accurate, it's more for fun to see what they "assume" the dog is.

 

Here are a few links to several websites that go into detail on this topic.

https://americanpomskykennelclub.org/knowledge-base/dna-discussion

https://bondvet.com/b/pet-dna-test

https://www.cbc.ca/amp/1.6763274

Should you be judgmental towards a breeder if any of their dogs don't test 100% on the breed verification portion of their dog's DNA test? Absolutely Not!!

Absolutely notTo judge a breeder negatively on this topic, without first educating yourself on the matter would be extremely small-minded and inconsiderate to all of the time and effort breeders have taken to ensure their dogs are as healthy as they can be.

If you feel that breed verification testing is accurate and that all purebred dogs should test 100% of their breed, then I am not the breeder for you. I would kindly advise you, to please find a different breeder. I will in no way, make any guarantees that any companies DNA breed verification testing is accurate. Nor will I entertain any accusations that my dogs are not purebred. AKC certification should be plenty for anyone. They are the only ones with stud books that go back generation after generation verifying the breed to be true. 

Below are some things highlighted that Embark says about the breed verification testing that they offer. Absolutely Not!!