Scientists have located the genes that make a poodle’s hair curly, and a collie’s hair long and straight.
No, this wasn’t just a way to ease the boredom of laboratory work, but part of a long-term project to figure out how genes cause disease.
The coats of domestic dogs vary widely — they can be long, short, straight, wavy, curly, wiry, smooth or a combination of different varieties. And that difference is exactly why cancer geneticist Elaine Ostrander decided to study dog hair.
Ostrander, who works at the National Human Genome Research Institute, wanted to know how genes create all this variety. So she studied about 1,000 dogs from about 90 different breeds.
She searched dog DNA the way a chef might compare recipes for souffle. What changed ingredient makes one different from the next? What mutation gives an Airedale terrier his curls and a golden retriever her tresses?
A Three-Gene Recipe
What Ostrander and her team discovered was that only three genes control all the different kinds of dog hair.
“You can go to the dog park, and every breed of dog looks different from every other breed, it seems,” says Ostrander. “Yet, you know, when we get down to the molecular biology, we really find that it’s a combination of three different genes that accounts for all that variation.”
This also has value in studying disease. Human and dog cancers are similar, so the fact that only three genes can create so much variation in hair might provide clues to how genes cause so many cancers in dogs and humans.
“Whether or not the exact same gene is mutated in humans doesn’t really matter,” says Ostrander. “It’s telling us the pathways that are involved, the kinds of genes that are involved, and the kinds of changes in those genes that lead to those diseases.”
The research appears online Thursday in Science Express.