Coat Color and/or Type

Merle is an incompletely dominant coat color pattern characterized by irregularly shaped patches of diluted pigment and solid color.

Harlequin is a pattern seen in Great Danes resulting from the complex interaction of the Merle and Harlequin genes on black pigment.

The Dominant Black gene (K Locus) affects pigment switching between eumelanin (black) and phaeomelanin (red or yellow) by interacting with the Agouti and MC1R genes.

“White” (cream-colored) Doberman Pinschers display a color dilution of the coat, eyes, and skin caused by a large deletion in the SLC45A2 gene.

Several gene variants are known to produce dilute coloration in dogs. Colors are lightened (diluted) to paler shades as a result of the variants' effects on pigmentation.

The Brown gene dilutes eumelanin (black pigment) to brown but does not affect phaeomelanin (red/yellow pigment).

The Agouti Signaling Protein (ASIP) gene interacts with the MC1R gene to control red (phaeomelanin) and black (eumelanin) pigment switching in dogs, affecting amount, type, and distribution of the two pigments.

The melanocortin 1 receptor (MC1R) gene controls production of the pigments eumelanin (black) and phaeomelanin (red/yellow). Six known variants of this gene are responsible for producing markings and coat colors including melanistic mask, grizzle/domino, black, and shades of red/yellow.