Dogs and people have more in common than a love of Frisbees and long walks on the beach. A new study reveals that some dogs, like some humans, carry a genetic mutation that causes albinism – a condition that causes little or no pigment in the eyes, skin, and hair.
The study conducted by researchers at the University of Michigan identifies the exact genetic mutation leading to albinism in the Doberman Pinscher, a discovery that has escaped veterinarians and dog breeders until now. Interestingly, the same mutated gene that causes albinism in this dog breed is also associated with a form of albinism in humans.
“What we discover was genetic mutations that make a missing protein required for the cells to be pigmented,” said Paige Winkler, a doctoral student at Michigan State University's Veterinary Faculty in East Lansing, Michigan.
Winkler said that the gene mutation found in Doberman Pinscher is responsible for a condition known as oculocutaneous albinism that also affects humans. The condition conveys definite characteristics in both humans and dogs.
“With a Doberman albino, you see a white or lighter-colored coat, pink noses and lips and the pale iris in the eye,” Winkler said. “These characteristics are very similar to the characteristics humans display with this particular condition, causing skin and hair slightly pigmented, and discoloration of the eyes and blurred vision.”
Just as people with this type of albinism experience skin sensitivity to sunlight, which can cause increased susceptibility to skin tumors, it was also found that canines with the gene mutated could be at increased risk of developing tumors of the skin, according to the researchers.
“We knew that albino Dobermans generally develop these types of tumors, such as humans [albino], but we wondered what was the actual increase in prevalence between a” white “dog and a regular-colored Doberman,” said Joshua Bartoe, an assistant professor in the Department of Small Animal Clinical Sciences at Michigan State University, who led the study. “What we discover was an important increase in the risk for growth of melanoma-like tumors in the albino dogs.”
These results are based on a study of 40 Doberman pinschers – 20 albino dogs and 20 “regular” dogs. Researchers found that more than half of the albino dogs had at least one tumor, while only one regular colored dog had a tumor.
Both researchers also said that their study could be an important asset for Doberman breeders around the world, especially the American Kennel Club, a purebred pedigree dog registered in the United States, does not register albino dogs.
“Because dobermans may carry the defective gene but show no signs of [condition], this has posed serious problems for breeders,” Bartoe said. “But now that we have identified the mutation, we can examine the genetic makeup of these dogs to determine if they could be carriers.”