Clinical Comments: A melanistic mask (also referred to as a mask or masking) is a dog coat pattern that gives the appearance of a mask on the dog's face. Black mask is a characteristic pattern in which red, yellow, tan, fawn, or brindle dogs exhibit a melanistic (black) muzzle which may extend up onto the ears. The hairs on the muzzle, and sometimes entire face or ears, are colored by eumelanin instead of pheomelanin pigment. Melanistic mask is inherited in several breeds as an autosomal dominant trait and may be a fixed trait in a few breeds of dogs.

Veterinary Comments: Black mask is a characteristic pattern in which red, yellow, tan, fawn, or brindle dogs exhibit a melanistic muzzle which may extend up onto the ears. Melanistic mask is inherited in several breeds as an autosomal dominant trait, and appears to be a fixed trait in a few breeds of dogs... All dogs with a melanistic mask had at least one copy of a valine substitution for methionine at amino acid 264 (M264V) and none were homozygous for the premature stop codon (R306ter). These results suggest that black mask, but not brindle, is caused by a specific MC1R allele. (Schmutz et al, 2003)