What is the difference between a Harlequin and a Fawnequin?

The main difference between a standard Harlequin and a Fawnequin lies in the dog’s underlying base coat color and how the Harlequin gene interacts with it.

Standard Harlequin A classic Harlequin Great Dane typically has a black (or sometimes blue) base coat. The Harlequin gene removes the dilute, grayish background color typically seen in a merle dog, turning it pure white. As a result, a standard Harlequin visually appears as a dog with a pure white coat covered in torn black (or blue) patches. Genetically, these dogs have the merle and harlequin genes (typically HhMm) acting upon a dark pigment base.

Fawnequin A Fawnequin is a Harlequin dog that possesses a fawn (sable) base coat. The Harlequin modifier is highly unique among merle modifiers because it affects both eumelanin (black/blue pigment) and phaeomelanin (red/tan pigment). Therefore, when a dog inherits the genetic instructions for a fawn coat (usually A 

y

 A 

y

 ) alongside the Merle and Harlequin genes, the entire coat pattern is altered.

Visually, a Fawnequin has a pure white base coat with tan or sable patches, rather than black patches. These fawn patches appear exactly where a standard black-based Harlequin would have had black spots. A Fawnequin may also have some black patches interspersed where normal black merling would typically show. Genetically, a Fawnequin combines the fawn base and often a masking gene with the merle and harlequin modifiers (resulting in a genotype like A 

y

 A 

y

 E 

m

 E 

m

 HhMm)