A melanistic mask is just a fancy term used to depict a dog who has a distinctive marking on the face. As the name implies, it gives the impression of a dog wearing a mask.
Several dog breeds are predisposed to displaying a melanistic mask, so let's discover what dog breeds display this and what it looks like!
A Lesson in Coat Color Genetics
To better understand melanistic masks in dogs, it helps to first get a little more acquainted with how a dog's coat gains its color in the first place.
Dogs, just like people, are known for producing a special pigment that is known as melanin. It is thanks to melanin therefore that humans and dogs have different colors of skin and hair.
In particular, there are two types of melanin that are responsible for coat color in dogs: eumelanin and pheomelanin.
The Effect of Eumelanin in Dogs
Eumelanin, when unaltered, by default results in very black color. When we see black areas on a dog we are therefore looking at the result of cells producing eumelanin (such cells are known as melanocytes).
However, there can also be variations in eumelanin as as a result of genes. The black color can therefore be diluted into blue (grey) or isabella (lilac). As a result of genes, black may also be softened into liver (chocolate).
Eumelanin is also responsible for conferring color to the dog's eyes and nose. Brown eyes and a black nose are therefore the result of eumelanin. When eumelanin is diluted, it leads to a dog with amber eyes (which is similar to hazel eyes in humans).
One big advantage of unaltered eumelanin is that it acts as an antioxidant, lowering the harm exerted by exposure to the sun. This is the main reason why many breed standards put a strong emphasize on a dog's nose being black with other colors often penalized.
The Effect of Pheomelanin in Dogs
Pheomelanin, on the other hand, by default results in a reddish-yellow coat color. Pheomelanin therefore is responsible for the "red" coat seen in Irish setters. However, just as in eumelanin, genes may alter its concentration and lead to softer shades such as tans, creams, yellows, golds and oranges.
Pheomelanin though can also be darkened resulting in a dark, rich mahogany color.
One main disadvantage of pheomelanin is that, unlike eumelanin, pheomelanin produces free radicals when exposed to the sun.
Unlike eumelanin which also confers color to the dog's eyes and nose, pheomelanin only gives color to the dog's coat.
In dogs, therefore, coat color for a great extent depends on the variations of concentrations of eumelanin and pheomelanin. In most cases though, dogs have both eumelanin and pheomelanin in their coats.
Melanistic Masks in Dogs
A melanistic mask in dogs, as the name implies resembles a "mask" considering that it covers certain areas of the dog's face. The term melanistic, refers to the black pigment that characterizes this facial feature. However, a melanistic mask can also be of any diluted color such as liver, blue or isabella.
More precisely, a melanistic mask in dogs is expected to include the hairs on the dog's muzzle, face and sometimes involves as well the dog's ears.
A melanistic mask often accompanies certain coat patters such as dogs with red, yellow, tan, fawn, or brindle coats.
Research has revealed that a mutation in MC1R causes the melanistic mask in dogs. More precisely, according to University of California, Davis, Veterinary Genetics Laboratory, dogs with the Em variant at the MC1R gene will produce melanistic face mask markings.
However, how visible the mask will be ultimately depends on the dog's coat color and whether or not expression of the gene is overridden by other genes. For instance, the mask won't be noticeable in a dark coated dog.
Did you know? The presence of a melanistic mask has been associated with premature greying of the muzzle in some dogs.
Dog Breeds With Melanistic Masks
According to research, a melanistic mask is inherited in several dog breeds and appears to be a fixed trait in a few breeds of dogs. Dog breeds often seen with a melanistic mask includes the following:
- Afghan hounds
- French bulldog
- German shepherd
- Great Dane
- Rhodesian ridgeback
- Tibetan spaniel
Did you know? Facial markings in dogs aren't there just for decoration! Discover the social function of facial markings in dogs.
Common Clinical Presentations in Dogs and Cats By Ryane E. Englar · 2019
Schmutz SM, Berryere TG, Ellinwood NM, Kerns JA, Barsh GS. MC1R studies in dogs with melanistic mask or brindle patterns. J Hered. 2003 Jan-Feb;94(1):69-73. doi: 10.1093/jhered/esg014. PMID: 12692165.