Mary Allen
Husky’s bright blue eyes are eye-catching. Only a few other dog breeds, such as the Australian Shepherd and Collie, can also have blue eyes. As for Siberian Huskies, researchers have now determined what their coloration often leads to. According to this, there is a close relationship with the duplication of a specific region on chromosome 18. The genome of dogs is distributed over a total of 78 chromosomes, 46 in humans and 38 in cats.
Several gene variants, such as the so-called merle factor that causes blue eyes in certain dog breeds, were already known, but they do not play a role in Siberian Huskies. A team led by Adam Boyko and Aaron Sams of Embark Veterinary in Boston, Massachusetts, a supplier of dog DNA tests, now included more than 6,000 dogs with different eye colors in the genome analysis.
The doubled region of the chromosome is close to the ALX4 gene, which plays an important role in the development of eyes in mammals, the researchers report in the journal PLOS Genetics. However, not all Huskies with the genetic variant have blue eyes, so other previously unknown genetic or environmental factors must also play a role. Often an animal has one brown eye and the other blue.