Horse colors and patterns can be confusing — here are some guidelines to get you started.
by Kristin Berkery
orses come in all kinds of colors and patterns, and even the most experienced horse enthusiasts will occasionally come across something so unusual that it stumps them. (Thank goodness for DNA testing.) But there are some basic rules of coat color genetics that you can always count on. If you have additional ones to share, please comment at the bottom of the article.
Grey: A dominant
*Aramus, Wayne Newton's homozygous grey Arabian stallion. Note the porcelain white color that's common to mature homozygous greys. Photo by Johnny Johnston
gene, grey will always express itself over other color genes if a horse inherits the grey gene. It’s not possible for a horse to carry a recessive (and therefore unexpressed) grey gene, so all grey horses have at least one grey parent.
Some horses are homozygous grey, meaning they carry two grey genes and can only pass grey on to their offspring. Since grey is dominant over other colors, a homozygous grey will always produce or sire grey offspring. Homozygous greys can be found in Lipizzans and Arabians, among other breeds.