Champagne Gene - Coat Colors

Coat Colors

Champagne is a dominant trait, based on a mutation in the SLC36A1 gene. A horse with either one or two champagne genes will show the effects of the gene equally. However, if a horse is homozygous for a dominant gene, it will always pass the gene on to all of its offspring, while if the horse is heterozygous for the gene, the offspring will not always inherit the color. Horses with the champagne gene may also carry other coat color genes that affect their phenotype, or outward color.

Horses with the champagne gene have a lightened hair coat and specific eye and skin color traits. Black pigment in the coat, if present, is lightened to chocolate, while red pigment is lightened to gold. The precise champagne dilute coat color produced depends on the underlying base coat color. The effects of champagne plus additional coat color genes have their own distinct vocabulary and appearances;

It is difficult to distinguish between homozygous and heterozygous champagne, which is different from incomplete dominant dilutions such as the cream gene. However the 2008 study that mapped the gene and identified it as a dominant trait noted in passing that homozygotes may have less mottling or a slightly lighter hair color. The authors of this study noted that

The following are considered the most "basic" champagne coat colors:

Classic champagne is, as its name suggests, the coat color most associated with the champagne gene. It is produced by the action of champagne on a black coat. The body coat is chocolate, the mane and tail a darker shade. The legs may also be slightly darker. The overall effect has also been described as lilac, dark taupe, and even green. This color is most often misclassified as grullo, and in the past was sometimes called "lilac dun."

Sable champagne is produced by the action of champagne on a seal brown coat. It is visually difficult to distinguish from classic champagne, and in the past was confirmed by a DNA test negative for the recessive black (a) allele at Agouti. Today, a test for seal brown can confirm this color.

Amber champagne is produced by the action of champagne on a bay coat. The coat is gold with chocolate points. Just as there are varying shades of bay, the gold body coat may vary in shade as well. The legs are often lighter than the mane and tail, and the colored points may be difficult to see. The mane and tail may also have "frosting" or light edges, a trait that also occurs in bay duns and some buckskins. Amber champagne can be confused with buckskin or bay dun.

Gold champagne is produced by the action of champagne on a chestnut coat. The coat is gold, and the mane and tail are typically ivory. In some cases, the mane and tail may be self-colored, matching the body coat. These gold champagnes are sometimes called "dark gold" and may be an all-over apricot shade. Dark gold champagnes can be confused with red dun, while those with paler manes and tails were historically called "pumpkin-skinned palominos."

Apart from the unique shades, there are several qualities of the champagne coat that may be used to help identify them. Champagne coats often have an unusual sheen. This sheen makes champagnes difficult to photograph accurately, as the appearance of the coat depends on the lighting. Not all champagne horses have this sheen, and there are many extremely shiny non-champagne horses, so a "sheen" in and of itself does not indicate the champagne gene. The coat may also exhibit reverse dappling, though this is also an unreliable indicator.