Eyes of a Different Color


blog post photo
Photo Credit: Patrick J. Kiger

I live in a canine-friendly town where people are allowed to bring their dogs into stores with them, which gave me the chance to meet this gorgeous one-or-two-year-old female Lab-pit bull mix. Aside from her pretty brown-and-white coat and long, lithe body, the striking thing about her is her differently colored irises. This characteristic is called heterochromia, and according to Slatter’s Fundamentals of Veterinary Ophthalmology, it’s caused in dogs by incomplete maturation or absence of pigment granules in the iris stroma or anterior pigmented layer. 


In humans, heterochromia is rare, as evidenced by the current fascination with actress Kate Bosworth. People sometimes develop the characteristic because of injury or disease, such as Waardenburg Syndrome, but in beautiful movie starlets and canines, it’s usually just a normal, healthy variation in eye color that has no effect on their vision. Veterinarian Race Foster writes in this PetEducation.com article that heterochromia is frequently found in a number of breeds, including Siberian huskies, Great Danes, Dalmatians, and malamutes. Cats sometimes have heterochromia too, as I learned from the Straying Around blog, which is written by an animal aficionado in Mumbai, India.