Champagne gene

The champagne gene is a simple dominant allele responsible for a number of rare horse coat colors. The most distinctive traits of horses with the champagne gene are the hazel eyes and pinkish, freckled skin, which are bright blue and bright pink at birth, respectively. The coat color is also affected: any hairs that would have been red are gold, and any hairs that would have been black are chocolate brown. If a horse inherits the champagne gene from either or both parents, a coat that would otherwise be chestnut is instead gold champagne, with bay corresponding to amber champagne, seal brown to sable champagne, and black to classic champagne. A horse must have at least one champagne parent to inherit the champagne gene, for which there is now a DNA test.

Unlike the genes underlying tobiano, dominant white, frame overo spotting and the Leopard complex common to the Appaloosa, the champagne gene does not affect the location of pigment-producing cells in the skin. Nor does the champagne gene remove all pigment from the skin and hair, as in albinism. Instead, the champagne gene produces traits known as hypomelanism, or dilution. Champagne is not associated with any health defects. Other dilution genes in horses include the Cream gene, Dun gene, Pearl gene and Silver dapple gene. Horses affected by these genes can sometimes be confused with champagnes, but champagnes are genetically distinct. Champagnes are not palominos, buckskins, or grullos, nor does the word champagne indicate that a horse is a shiny or light shade of another coat color.

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