Locus Em or melanin mask causes the black mask on the dog's face. This allele is dominant because only one copy is needed to express the mask phenotype. The mask can be tested for in any breed, but is most commonly found in the breeds listed below.
Transmission
Autosomal dominant
Breed
Afghan Hound, Akita, French Bulldog, Great dane, Great dane, Greyhound, Whippet, German Shepherd
