SAN FRANCISCO (KCBS)— A common question for potential dog owners who want to make the right decision is: how much of a factor should a breed be when choosing a dog? Dr. Jennifer Scarlett, co-president of the San Francisco ASPCA said it depends.

“If you know you want a certain size and look to a dog then breed is the way to go. If you’re looking for a particular behavioral trait, then things get fuzzy. The reason for that is, over the years breeders have bred for the look of the dog and de-coupled it from its function and behavioral traits,” she said.

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Scarlett explained that breed in dogs is similar to race in humans and that what is known is that we’re more genetically alike than we are different.

Dogs have 20,000 genes according to Scarlett and that only about one percent of those make up the look of the dog, but it’s the behavior part that is more of a “complex genetic puzzle” that hasn’t been figured out.

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Even animal experts can have a difficult time determining a dog’s breed simply based on physical appearance. Recently a researcher took mixed-breed dogs, or mutts, and DNA tested them to see what breeds were in them. Then veterinary professionals and other animal experts were then asked to predict what breeds were in the mutts. According to Scarlett, most of the experts, including herself failed miserably.

“This is important because we make a lot of medical decisions based on the fact that we think that it’s part boxer or spaniel and we also make decisions in shelters about who to put up based on how they look.

If you want to test your breed knowledge you can take the test here.

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