What breed an animal shelter thinks a dog may be is only right about two-thirds of the time, according to a new genetic study.
Researchers from Arizona State University collected DNA samples from 919 dogs in shelters in Arizona and California for analysis. As they report in PLOS One, they found that the most common breeds among shelter dogs there to be American Staffordshire Terrier, Chihuahua, and Poodle. They tested the animals using a commercially available test from Mars Veterinary.
About 5 percent of the dogs were identified as purebred — most commonly American Staffordshire Terrier, Labrador Retriever, or Yorkshire Terrier — while the others were mixed.
These genetic breed labels didn't always match with what breed shelter workers thought the dogs might be. The breed the works thought might be in the dogs matched with the most prevalent breed from the genetic analysis about 57 percent of the time and matched with the primary or secondary breed from the genetic analysis about 67 percent of the time.
What breeds dogs are labeled as affects how long they stay in the shelter, the researchers add, as people use breed information to gauge temperament.
But, senior author Clive Wynne adds in a statement that "[t]he genetics of behavior is so complex that a dog who is a cross of two breeds might not behave much like the typical members of either of its parents' families."