The study adds to growing evidence that such ancient mating events have sometimes played a vital role in the adaptation of modern species to their environments, the scientists say.
“It’s a very cool discovery … which turns out to be a mirror of what’s going on with the humans [there],” says Elaine Ostrander, a geneticist at the National Institutes of Health in Bethesda, Maryland, who was not involved with the study.
Researchers think that a dog breed from China traveled to the Tibetan Plateau about 24,000 ago. They adapted over this time to the icy climate, and formed into the hairy, large dogs we see today. In order to survive these temperatures, the dogs, along with the Tibetan people, produce less hemoglobin. Hemoglobin is the protein that carries oxygen in red blood cells. A variation of the gene, EPAS1, is what aids this adaptation. This variant helps reduce the chance of a clot or stroke when red blood cells try to make up for lack of oxygen.
The study shows that the gray wolves may have been the source for this variant. To test this prediction, researchers tested DNA segments from 29 different gray wolves. They noticed that the mastiffs were closely related to Chinese dogs more than they were to the gray wolves. Two other genetic areas in mastiffs were uncovered in the gray wolves as well.
This is definitely a very interesting article. This study reveals how people and animals have adapted to live in more extreme clients. The fact that both humans and the mastiffs have similar variants of the gene is very extraordinary in the world of genetics.