DNA breed testing and kennel club breeds
Perhaps the first consideration when understanding DNA "breed" identification is just what a "breed" is.
Most breeds have only existed for the last couple of hundred years. They have come about by selecting dogs for a specific look, use, colour or nature etc. By definition this eliminates unwanted genetic features. It does not result in new genes being created. There are no single DNA markers that identify a particular breed. Kennel club breeds, with few exceptions, are closed groups of related dogs and dogs outside of that cannot be added. Embark can use the length of genetic segments a dog shares with their reference dogs to see how many generations it has been since they last shared an ancestor. Long segments of DNA that are identical to known purebred dogs tell Embark's scientists that the dog being tested has a relative from that breed. By testing over 200,000 genetic markers, they build up the dog being tested genes one DNA segment at a time, to learn the ancestry. Other dog DNA tests look at many fewer genetic markers and have to take a guess at breed ancestry based on that. Just what DNA is in a breed can differ in different countries since not every dog in a breed has been used for breeding in geographically separated countries and some DNA may have been lost in one country but not another. It is therefore reasonable for the testing company to know what country a pedigree dog is from. The DNA test in such cases will confirm that the dog does or does not have any other mix in it. Likewise, a dog of unknown origin will reasonably give information of the mix, or otherwise. It is kennel clubs that decide and control what a breed makeup is and not DNA test companies. Likewise in a breed where an outside dog may be added, when that happens the DNA testing company will of course add that information to their DNA profile for that breed.
When it comes to our ancient origin dogs much the same applies. It would be impossible to test every such dog in every country and dogs probably do not move between these countries as often as in the past when dog were first introduced to these countries.
A recent comparison of some DNA test companies showed just how poorly some perform as linked below. The dog from Kuwait shows how many expats still fail to understand that free born dogs in the region are simply not mixes of the "breeds" they are familiar with. Embark remains the only company able to identify our village/desert/wadi/baladi dogs.
