When people migrate, domestic dogs follow them. But patching together the details of these migrations is difficult because the information is scattered across the genes of hundreds of dog breeds. However, in a Research Paper published April 25 in the journal Cell Communications, the researchers said they compiled a dog evolutionary lineage using genetic sequences from 161 current dog breeds. The dog genealogy provides new evidence that dogs have crossed the Bering Strait with their owners and are likely to have helped researchers identify genes that can cause both dogs and people to get sick.
The study also highlights how the oldest dog breeds evolved or were domesticated to play a role. "The first is to choose a breed, such as a shepherd or a Boeingda hound, and then add appropriate physiological characteristics to it." Study collaborator Heidi Parker, a dog geneticist at the National Institutes of Health, said.
Previously, the most popular dog breed in the Americas was thought to have European ancestry, but the study revealed that some breeds from Central and South America, such as the Peruvian Hairless Dog and the Mexican Hairless Dog, appear to have been the "New World Dog," a subspecies of dogs that crossed the Bering Strait with the ancestors of native Americans at the time. Scientists have previously reported archaeological evidence that New World dogs did exist, and the study found live evidence of their existence in existing dog breeds for the first time.
In addition, the researchers also found that many hound breeds, such as the Golden Retriever and the Irish Spy Dog, originated in Victorian Britain. At that time, the advent of new tools such as shotguns opened up new roles for dogs in hunting. And these dogs evolved next to each other in the tree species, similar to the Spanish Hound. Middle Eastern dog breeds such as the Saluki, as well as Asian dog breeds such as the Chinese Pastoral Dog and the Akita Dog, appear to have separated earlier than the Victorian era.
Ostrander and his colleagues spent years recruiting dog owners for research and sequencing the dogs' genes. "If we see an unsequenced dog breed, we go straight to the owner and ask' 'We haven't sequenced the Oda Hound yet, your dog is a beautiful Oda Hound, do you want it to be a representative of the Oda Hound in the dog genetic database?' Usually people will readily agree. Ostrander said.
But more than half of the dog breeds are still unsequenced, and researchers will work to fill that gap next. Moreover, understanding a dog's genetic history has practical uses. Dogs have long been victims of certain human diseases such as epilepsy and kidney disease, and dog genes have also helped to study these diseases. (Tang Yichen)