Blue Roan Horse Information

Color genetics in horses can be very confusing. While some breeders will just breed colored animals to each other and hope for a colored baby, this is not scientific. There are dozens of factors that go into coat color, each of them genetically controlled. Understanding the basics of the blue roan horse genetics is the key to this rare color.
  1. Features

    • A blue roan is a very beautiful and rare color. The horse has black legs, a black mane and tail, often a black head, and black "points." The body, particularly around the belly and flanks, has a wide scattering of white hairs--called roaning--which makes the coat look "blue" in the light. It is a unique look, and can be distinguished from other roans because there are no red hairs.

    Base Color

    • To be a true blue roan, the base coat color must be black. Genetically, this is symbolized by the "E" allele. The coat color red is symbolized by "e," but when paired with "E," the color is black. So the genetic reading for the base coat will be "Ee." A blue roan cannot be any other genetic coat color than "Ee" or "EE" (homozygous black).

    Agouti Gene

    • The agouti gene is the marker that determines what the body color will be. The simplest way to describe it is that to be a blue roan, the horse must have the allele "aa." This marker means that the body color will always match the legs, which in the case of the blue roan is "Ee" or "EE," which is black. If the horse has an agouti marker with an "A" anywhere in it, it will not be a true blue roan. The entire coat must be black to be a blue roan.

    Roaning

    • Finally, for a blue roan to truly be a roan, it must carry the roaning gene. This is signified by "Rr" or "RR." In the case of the "Rr" gene, the roan is recessive, so will only be passes along to half of that horse's offspring. In the case of "RR," the gene is dominant, and the offspring will always have roaning patterns in the coat.

    Identification

    • So, to properly identify a true blue roan, you need to be able to see a genetic test from a laboratory that shows that the horse carries the following patterns: "Ee" or "EE," "aa," and "Rr" or "RR." For the ideal breeding prospect for this rare color, the genetic pattern would be "EE aa RR." This would mean that the horse will always throw the black base color, never have any red in the body color, and always throw the roaning pattern.

    Significance

    • It is important to note that a blue roan is simply a horse. There is not a "breed" that is a blue roan. The horse is still judged on the same characteristics as any other horse: conformation, movement, and temperament. Blue roan does not indicate any special skill or personality. It is simply a rare coat color that is hard to reproduce, and beautiful to look at.