Mars is considered the leading authority in dog DNA analysis.
Mixed-breed dogs account for 53 percent of all pet dogs in the United States.
Mars said the most common DNA found in those mutts is that of a German Shepherd.
Other common mutt breeds include the Labrador Retriever, Chow Chow, Boxer, Rottweiler, Poodle, Terrier, Golden Retriever, Cocker Spaniel, and Siberian Husky.
