Horses appear in a variety of coat colors and patterns, varying from solid red, black, or white to dapples and pearls, and in patterns like appaloosas and paints. These colors and patterns are managed by genes that may be associated with undesirable flaws or defects that can be fatal, such as the Lethal White Syndrome. Because deoxyribonucleic acid testing is now available to horse breeders, owners, and veterinarians, it is important to understand the fundamental concepts of dominant and recessive genes, genetics, and the potential for flaws to be expressed. Genetic testing can be performed to satisfy curiosity or to implement life saving measures to prevent the death of an offspring.
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