Dog Gone Genetics: A Few Genes Control Fido's Looks
"Humans are complicated genetic jigsaw puzzles. Hundreds of genes are involved in determining something as 
basic as height."
"But man's best friend is a different story. New research shows that almost every physical trait in dogs — from a dachshund's stumpy legs to a shar-pei's wrinkles — is controlled by just a few genes."
"Writer Evan Ratliff has been looking into dog genetics for National Geographic Magazine. He tells weekends on All Things Considered host Guy Raz that that quirk makes it extremely easy for breeders to develop new, custom-designed dogs — like the German hunters who bred the original dachshunds a few hundred years ago."