There's a new pet friendly product hitting the market called Wisdom Panel, which is sold in pet stores like PetSmart as well as select vet offices, is taking the guesswork out of determining mixed-breed puppy's heritage.
This product, which retails for about $80, is a do-it-yourself kit that allows you to send in a DNA swab from the inside of your dog's cheek. WisdomPanel then tests the DNA and prepares a report, which is made accesible online. The report details the types of breeds that your pet decends from, and highlights potential health problems that could result from the mix.
Because of its ability to identify percentages of breeds involved in a dogs' DNA, it could be particularly useful for people traveling internationally with pets. Some countries, like Singapore, require photo proof of mixed breed dogs prior to import in order to make sure they are not mixed with one of the "banned breeds" -- usually a breed that is considered aggressive. Having this test showing the exact mix of breeds would be another precaution to make sure your pet won't run into trouble in his new country!