Molecular characterization of the Himalayan mink.

A rare color variant of the American mink (Neovison vison), discovered on a ranch in Nova Scotia and referred to as the "marbled" variety, carries a distinctive pigment distribution pattern resembling that found in some other species, e.g., the Siamese cat and the Himalayan mouse. We tested the hypothesis that the color pattern in question-light-colored body with dark-colored points (ears, face, tail, and feet)-is due to a mutation in the melanin-producing enzyme tyrosinase (TYR) that results in temperature-sensitive pigment production. Our study shows that marbled mink carry a mutation in exon 4 of the TYR gene (c.1835C > G) which results in an amino acid substitution (p.H420Q). The location of this substitution corresponds to the amino acid position that is also mutated in the TYR protein of the Himalayan mouse. Thus, the marbled variant is more aptly referred to as the Himalayan mink.