Health Issues in Dogs with the Merle Gene

Dogs with merle gene show a mixture of color on their coats such as black and white patches, brown and white patches, and sometimes a mixture of brown, black and white. The newest addition to our family, Tucker, is a blue merle australian shepherd. His coat is black and white with a little bit of brown. He has the prettiest blue eyes I have ever seen with pink/black rims. The issue of blue merle or any species of dog with the merle gene is that they can have ocular and auditory defects. Dogs that are homozygous for the merle gene are called “patterned whites” or “double merles” and are merles with more white than they should have and generally suffer from ocular problems. This can be either partially blind or fully blind. This generally shows up in dogs that have blue eyes rather than brown. Luckily Tucker, is a patterned white and has blue eyes but does not suffer from hearing loss or blindness. Blue eyes are more sensitive to sunlight which can also cause blindness. If the rims around the eyes are pink they can be burned and can also lead to eyesight issues. Thankfully they have come out with a product called “doggles” which are sunglasses for dogs. Yes, Tucker has doggles and he is the coolest puppy in the neighborhood.

Source: “Eye defects in Australian Shepherds”. Retrieved 16 April 2011.