Ancestry tests aren't just for humans anymore. We went to Petco this weekend to buy dog food and found brochures for doggy DNA testing. Now, those of you with dogs of uncertain parentage need puzzle no longer. According to Petco, their SNP test (what is a SNP?) can identify over 100 different breeds and they'll tell you which breeds are represented in your dog and whether your dog's breeding is mixed (or pure).
The brochure from Petco also claims that knowing something about your puppy's parentage could be helpful in understanding their behavior and potential health risks. That's probably true to some extent, since many behavioral traits and health problems have a genetic component. I'm not sure how important that information is for everyone, but we were glad to have it with our dog.
We learned about our current dog's parentage through a more traditional route - from the owners. We knew when we met the puppies that their mother was a lab and their father, a Chesapeake Bay Retriever. We read everything we could find about Chessies and were forewarned by articles on their less pleasant traits. It was helpful to know ahead of time that our cute little puppy might grow up to be an assertive dog with a strong need for obedience training and lots of exercise. If we hadn't known that Chessies could be aggressive, we might have taken fewer precautions and spent less time in puppy school.
I don't think these tests have quite enough power to help the little Boogers find out it they're really clones, but at least someone could tell if they're Staffordshire Terriers or not.
Update: Pet DNA testing has grown a bit. Biotech-Careers.org shows seven companies offering DNA testing for pets. Cats can get their DNA tested, too.