Roan (color) - Roan Dogs

Roan Dogs

The genetics behind roan dogs are still unclear, and at present candidate genes have been ruled out. There remains a great deal of ambiguity in terminology regarding mottled dogs, which are called roan, ticked, mottled and belton depending on the context. The roan or ticked color is described in many breeds of gundogs such as English Cocker Spaniels, American Cocker Spaniels, English Springer Spaniels, Field Spaniels and Brittanys, German Shorthaired Pointers, Spinoni Italiani, Lagotto Romagnolos and English Setters, as well as Border Collies and many other breeds.

In dogs, roan manifests itself only in unpigmented areas, the presence and shape of which are determined by other genes. This is in stark contrast to true roan horses and roan cattle, which are roan only in pigmented regions of their coat and may have white markings. Instead, dogs with roaning or ticking are born with clear, open white markings which begin to fill in with flecking in the subsequent weeks and continue to darken with age. Most breed standards use the terms "ticked" and "roan" interchangeably, with the former referring to clearly defined flecks on a white background and the latter to flecks so closely spaced that the mixture appears even. The terminology that relates the underlying coat color with the roan modifier is often breed-specific, but most standards call a black dog with roaning blue. In breeds that are characterized by roaning and ticking such as the Large Munsterlander, clear white-marked individuals may be called plated. The term belton is reserved for English Setters.

In 1957, Little suggested that roan and ticking were controlled separately, and postulated that roan may have been homologous to "silvered" coat in mice. This condition in mice is actually homologous to merle, which might be described by some as "roan." In 2007, the gene responsible for roan cattle (KITLG) was refuted as a possible cause of roan in dogs. Neither roan nor ticking, if they are independently caused, appear to be recessive.