
I have said in previous posts that it is important to know the genetic make-up of your mixed breed dog because it provides clues into your dogs behavior. For example, Labs, like all retrievers are mouth oriented because they are bred to do a certain job...retrieving. And so you have an explanation as to why your Lab mix chews on everything he gets his mouth on...it isn't displacement behavior, it is his genetic make-up. But if your Peke/Pug mix is chewing up everything, then something is wrong and you better get to the bottom of it fast before the behavorial issue becomes a habit.
It has become increasingly popular lately to have your dog's DNA tested to identify the dogs genetic background. And I applaud that. But I also wonder just how accurate these tests are.
Yes, I have read the manufacturers claims as to accuracy. I have also noticed that some of the manufacturers do not have the ability to read genetic markers of all the pure breeds.So if your dog is 50% Greater Swiss Mountain Dog and the DNA Test isn't able to recognize that breed, then how accurate is it?
The dog pictured above is a case in point....the dog group that rescued him swabbed his mouth, sen
t it off and the response was that he is mostly Doberman and Yorkie...yep, that is what I said....Doberman and Yorkie, wow I would have liked to have seen that liason....perhaps the Yorkie used a ladder.
t it off and the response was that he is mostly Doberman and Yorkie...yep, that is what I said....Doberman and Yorkie, wow I would have liked to have seen that liason....perhaps the Yorkie used a ladder. So let's break this down...now I am not a geneticist, but having bred champions and studied canine genetics for most of my life here is my take on this dog...

The dog's color is red background with black brindle. How many Yorkies do you know who are brindle? None! Yorkies do not carry a brindle gene...they do carry a black and tan gene. As do Papillons.The dog also had a tiny percentage of supposedly Papillon in him.
Now, as I already stated, the Yorkies are silver/blue and tan...this is a dilution of the standard black and tan gene. Yorkie pups are born black and tan, then as they mature the dilution gene fades the black color to steel blue or in some cases silver. (Dilution genes occur in a variety of breeds and produce a lot of different color effects. One you may be more familiar with is a black Poodle who will often times become silver upon maturity.)

Dobermans also carry a black and tan gene. (In red Dobes, the color becomes red and tan, in blue Dobes it is blue tan ( from a dilution gene) and in white (albino) Dobes there is a masking gene,(not a dilution gene) which prevents any color from manifesting, but genetically the dog is still masked color with masked tan markings. So, here we have a brindle dog who genetically is primarily made up of two breeds with highly dominant black and tan genes, and secondarily one who also can carry a black and tan gene (and a parti-color gene but we won't go there ). Doesn't make sense does it? Normally when you combine black and tan genes with brindle genes you get a dog whose tan markings are brindle but the rest of the color pattern is normal... we also have the unlikely liason of a 70 pound Doberman and a 5 pound Yorkie...that doesn't make sense either. And nothing in the supposed background of this dog has a brindle gene yet here is a brindle dog. We do have 3 breeds of dogs that all carry black and tan genes. Remember,two of which, the Dobe and Yorkie breeds, carry them dominantly.
Then there is the dogs conformation. The red arrow points to an arch over the dogs loin. An arched loin is not a conformation feature that you will commonly find in Dobes, Yorkies or even the Papillon. The blue arrow points to the stop, yep, that is the name of the area pointed to on this dogs head, and his stop is extreme, while a Dobes would be only slight. And the muzzle is too long to be influenced by Yorkie or Papillon genes.
(Pictured here is a typey Doberman head notice the slight stop...) The brindle dog's head is what we call c
heeky. In addition, he has no fill in the front of his chest. The set of the dogs stifle does not reflect any Doberman/Yorkie influence either. These are some of th
e things that make me think the brindle dog has no Doberman or Yorkie or Papillon in him at all but is a Rhodesian Ridgeback /Whippet mix. A liason much more likely. (purebred photos from AKC)
..also check out this you tube video, the Am Staff in the video is of the highest quality,and the DNA test she used is NOT the brand used on the brindle dog in this post...
http://www.youtube.com/watch?v=4a4CDvK868w
http://www.youtube.com/watch?v=4a4CDvK868w