Roan (color)

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Different meaning: Roan, Norway.

A red roan horse

Roan is a type of coat color in horses (and, occasionally, in other animals, such as dogs and cattle) that is a mixture of white hairs with a base coat of another color.

1 Roan in Horses
2 Lethal Roan Question
3 Roan in Dogs
4 Roan Cattle
5 See also
6 External links

[edit] Roan in Horses

Roan, caused by the roan gene, (R), consists of single white hairs intermingled with the base color of a horse. Roaning gives the horse a lightened appearance, while the mane, tail and head tend to remain darker, close to the original base color. Roan horses also tend to have dark lower limbs, and the top of the dark area may have a pointed or triangular appearance. It is a dominant gene, meaning that at least one parent must be a roan in order to pass the gene on (it does not appear from two non-roan parents with roan lineage).

see also Equine coat color genetics

The true roan gene appears in some breeds more than others. Roans are commonly found in Quarter Horses, American Saddlebreds, Tennessee Walking Horses, Connemara Ponies, Miniature horses, American Paint Horses, Welsh Ponies (though rarely, if ever, in Welsh Cobs) and Shetland Ponies. There are only two roan Morgan horses known to be alive today, a gelding and an aged mare, so the color is probably at a dead end in that breed.

Strawberry roan

The roan gene arguably does not appear in Arabians and Thoroughbreds; though horses in these breeds have been registered as "roan." It is thought that irregularly colored individuals in those breeds may actually carry the rabicano or sabino gene complex rather than the "true" roan gene.

Several terms are used to describe different shades of roan.

see also Equine coat color

Strawberry Roan Begins a chestnut base coat with white intermingled hairs. Some Strawberry roans have a pinkish tint.
Red Roan Begins with a bay base coat, giving a roan horse a reddish coat and black or very dark "points" (mane, tail, head and lower legs). Some dark Strawberry Roans are also called Red Roans.
Blue Roan Begins with a black base coat and the end result is a horse coat with a bluish tint.

These shades of roan are created genetically as follows:

Red base (chestnut) + Roan = Strawberry Roan (sometimes called a Red Roan)
Black base + Roan = Blue Roan
Bay (black base + Agouti gene) + Roan = Red Roan

Roan can also appear on any base color or mixture of colors, so there are also buckskin roans, silver dapple roans, etc. Contrary to some belief, the varnish roan coloring is not caused by the roan gene, but the result of the varnish roan gene combined with an appaloosa (normally spots, blankets, etc.) coloring. Also see "Varnish Roans"

[edit] Lethal Roan Question

The idea of "Lethal Roan Syndrome" came from a 1979 study (Hintz, H.F. and VanVleck, L.D., published 1979. Lethal Dominant Roan in Horses. Journal of Heredity 70:145-146.) This study, based on percentages of roan foals thrown by roan parents, popularized the idea of Lethal Roan Syndrome. The study did not include direct genetic analysis and assumed fetus absorption preventing birth.

A recent genetic study of roans by Dr. Ann Bowling (See http://www.hancockhorses.com/article-roanQHNews.pdf) refuted Hintz and VanVleck’s inferences. Using genetic analysis, Dr. Bowling found several homozygous roans and no evidence of a Lethal Roan Syndrome.

[edit] Roan in Dogs

The roan gene in dogs acts as a simple dominant gene. The action of the gene results in a mingling of colored and white hairs. To be roan a dog must have white areas; a solid colored dogs can not be roan. Breeds where the roan gene commonly occurs are English cocker spaniels, English setters, Australian Cattle dogs. The roan pattern also occurs in American Cocker Spaniels, Field spaniels and Border collies.

Roan dogs are more prone to deafness due to the absence of pigment present during ear formation. There are no other health issuses associated with this gene. Black and white roans are referred to as "blue roans" (spaniels) or "blue belton" (English setters). Red/buff and white roans are referred to as "red roans" "orange roans" or "lemon roans" or oran. Brown and white are referred to as "liver roans", "chocolate roans" or "brown roans".

[edit] Roan Cattle

The roan colour can also result in Shorthorn Cattle, but in a case of intermediate inheritance or Codominance. These cattle can not breed true, as this type of intermediate inheritance is also Heterozygous, or hybrid, as two different colour alleles are required form the parents to produce this particular coat colouring.