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Blue Roan Horse Color Genetics with Photos and Descriptions

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Roan horses are undeniably gorgeous. Having coats on their bodies comprised of equal parts colored fur and white fur, the effect created is stunning. Roans actually come in different colors: red and blue and, more recently, bay roans have been included to cover the darker brown roans that were once lumped into red roans. Each coat variation is distinct and unique, with the blue roan being especially recognizable.

Blue Roan Horse
Blue Roan – BLM Mustang – Little Owyhee Herd Area

What Exactly Is a Blue Roan Horse?

A blue roan has a coat that is a 50/50 mix of white and black hairs in their coat. That’s right – a blue roan is not actually an indigo coated horse, but rather one with a dark, black base. This mix of black hairs and white hairs gives the horse a blue-hued appearance, hence the name.

When it comes to the mane, tail, head and lower legs of a roan, the white hairs are less present – or absent entirely. But the background coat color for a blue roan is always black.

Blue roans are always roan at birth, though they can appear to be born solid black and then shed their baby coat to reveal their roan color.

Often, the term roan is miss-attributed to horses that are not actually roans, but, rather, have patterns that are considered to be “roaning”. These horses are usually sabino (a paint gene) or gray.

In fact, the Jockey Club, which registers Thoroughbred horses, has been registering gray horses as “Gray or Roan” for centuries, even though a true roan didn’t exist until Lilac Hill was foaled in 2000. (source)

Blue Roan vs. Red Roan

The simplest difference between the two colors is, of course, that blue roans look blueish and red roans look reddish.

While blue roans are born with a black undercoat, red roans can possess a coat that is chestnut, bay or in between.

In the past, “strawberry” was a term used to refer to pinkish colored roan. Most often these were horses with a chestnut or sorrel base coat.

“True” Blue Roans

True Blue Roan Half Arabian / Half Quarter Horse
True Blue Roan Half Arabian / Half Quarter Horse – DNA Verified to be Roan not Gray – Mom is a Bay Arabian and dad was a Buckskin Roan – Photo by the Author

A true blue roan is a true roan on a black coat. True roans are described as classic and they do not include the patrials or patterns, such as varnish, rabicano or sabino.

This means the horse has an even mix of white and black hairs across their full bodies (excluding the legs and face). Further, the coat color remains consistent and, while it may change shade based on the season, it does not get consistently more gray or more white as time goes by.

True roans are genetically distinct from the other patterned roans. So, not only are true blue roans distinct in appearance, they are actually different in their genes. To understand this better, let’s have a look at the genetic makeup of a roan horse.

Roan Coat Color Genetics

A roan coat is determined by coat color genetics. The roan gene itself is a dominant trait (Rn) and the foal of two non-roan parents, even if they have a bloodline of roans behind them, cannot have the roan trait present in them.

There are many unique roan variations but, most stock horse registries recognize three distinct types for registration purposes. These are Blue Roan, Bay Roan, and Red Roan.

Roan on a Chestnut Horse is a Red or Strawberry Roan
Roan on a Chestnut Horse is a Red or Strawberry Roan – AQHA Mare – Photo by the Author

All horses are born with a red or black base. They also either have an agouti gene or they don’t. Agouti is kind of a funny word if you haven’t heard it before so let me explain.

Agouti, represented as capital “A” when present, and lower case “a” when not present, is responsible for turning a black horse bay. Agouti has no effect on red-based horses (like chestnuts).

Roan on a Bay Horse
Roan on a Bay Horse can be called a “Red Roan” but is more accurately described as a “Bay Roan” – BLM Mustang Gelding – Photo by the author.

Remember that all genes come in pairs. Since there are three primary base roan colors, roans are typically lumped into the one that best fits their base color.

Base ColorBlack GeneAgouti GeneRoan Variation
BlackEE or EeaaBlue Roan
BayEE or EeAA or AaBay Roan
ChestnuteeAA, Aa or aaRed Roan

Dominantly inherited genes can’t skip generations. As mentioned, two non-roan parent horses can’t produce a roan baby.

However, there are times when it may look like a roan coat has skipped generations. In those cases, it turns out that one parent was actually slightly roaned, but the coloring was incredibly slight or, alternatively, their true roan nature was masked by an overabundance of white markings, making them look not really roan.

Roan Imposters

There are some horse coat colors that look like roan but, looks can be deceiving. Here are the four most common ones.

This pinto BLM mustang looks like she has roaning over her neck and withers but she does NOT carry the roan gene.
This pinto BLM mustang looks like she has roaning over her neck and withers but she does NOT carry the roan gene. Photo by the author.

Sabino (also called Sabino Roan)

Some sabino horses express their coat color in a way that makes it appear that they are roan. The sabino gene can be minimally expressed, so that you don’t even know it is there, or maximally expressed, where it is very obvious.

The thing is, a maximally expressed sabino could look like a true roan. In fact, this is fairly common in purebred Arabian horses where the roan gene does not exist.

Many other breeds experience patterns that are irregular patches of white with rough edges known as sabino. These markings can have borders that are roaned quite heavily and can be mistakenly classified as a roan.

Rabicano

Another pattern is called rabicano. Unlike a true roan that will have an even mix of white hairs all across their main body, rabicano has white hairs that are more clustered around the base of the tail and on the flanks.

Horizontal white hair stripes can be seen at the tail’s base. Rabicano patterns are found in many breeds, and Arabians that are actually rabicano are often mistaken for roan. It is also often found in Thoroughbreds.

Varnish Appaloosa

This Varnish Roan Appaloosa does NOT have the roan gene.
This Varnish Roan Appaloosa does NOT have the roan gene. Photo by the author.

A varnish roan can be found in breeds with appaloosa characteristics. This is one type of the leopard complex coat color that’s an all-over blend of white and colored hairs. 

In a varnish roan appaloosa, patches of skin that are closely adhered to the skeleton, such as on the face or at the legs, do not grow as much white hair.

These darker patches are often called “varnish marks” – these are not found in horses that are true roans.

You can determine a varnish roan from a true roan by noting the presence of those leopard complex characteristics, such as striped hooves or mottled skin around the eye and their nose.

Gray

When gray horses are foals and even in their younger years, they can often appear to be roan instead of gray. As I mentioned above, the Jockey Club routinely registers horses as “Gray or Roan”.

Like a roan, a gray horse must have a gray parent. Gray is another color that is dominate and cannot skip a generation. So, if your foal looks roan and has at least one parent that is gray, further investigation is warranted.

This foal appears roan but is most likely gray just like his mother.
This foal appears roan but is most likely gray just like his mother.

To Complicate Matters

To complicate matters, each of the four “roan imposters” listed above can exist in combination with the roan gene. So a horse can be roan and turn gray. Likewise, a horse could be varnish appaloosa and roan.

In fact, it is theoretically possible to have a horse that has all of the genes above. This is one of many reasons horse coat color genetics is so fascinating to learn!

Exceptions to the Roan Parent Rule

I do want to make a quick note about the roan parent rule. It is safe to assume that a roan horse MUST have a roan parent. Roan always expresses itself in some fashion when present and, if a horse has it, they can pass it.

Sometimes, a foal is born that is gray, registered as gray, and starts producing roan offspring with non-roan mates. This almost always means that the gray horse is also roan. The same could be true for any of the pseudo roan colors.

I say almost always because there is a very small possibility that an individual roan horse could be produced from a non-roan parent through gene mutation. This is, in fact, how the roan gene came to even exist in the Thoroughbred breed.

Keep in mind that you are more likely to win the lottery and be struck by lightning on the same day than have a foal that happens to have a random gene mutation resulting in the foal being roan with non-roan parents.

How to Get A Blue Roan Horse

The easiest way to get a blue roan horse is to buy one. That being said, if you want to try and breed your mare or stallion for a blue roan foal, here are some things to consider to increase your chances.

If either parent is homozygous for agouti (AA) there is zero chance of producing a true blue roan foal. The first thing you need to do is test your own horse for red and black. This will help you choose the mate that will give the best possible chance for a blue roan foal.

Be sure to read my article on equine DNA testing which includes a list of reputable labs that can perform this coat color test for you. The test is easy and only requires you to mail in a hair sample.

Once you know your horse tests either Aa or aa for agouti, your single best shot of getting a blue roan foal is to find a blue roan mate that is both homozygous for roan and homozygous for black. This guarantees the foal will be black based and carry roan.

What that doesn’t mean is that your foal will be roan. This depends on whether either horse carries any other color modifying genes.

In addition, if your horse tested Aa, there is a 50% chance of passing on the dominant agouti gene to the foal which would result in a bay roan instead of a blue roan.

Blue Roan Horse Breeds

There are a variety of breeds that produce true roans. These include many European draft breeds such as the Brabant, Italian Heavy Draft, Rhenish-German Cold-Blood, etc.

Blue Roan horses are also quite common  in North American breeds such as Paint horses, Paso Finos, the Quarter Horse, Standardbred, Mustang, and Tennessee Walking horse.

Also, British ponies often carry the gene. You can see roans in Welsh ponies, Gypsy cobs, Shetland ponies and many more. Even adorable little mini horses can be roans!

However, keep in mind that some breeds do not have the roan gene at all. This includes the Arabian horse, Suffolk Punch, Hafflinger. While some may be born with roan-like coats, they are not actually roans.

redman quarter horse stallion
Red Man – AQHA Stallion

Some famous roan horses include Red Man, born in 1935, and stallion Blue Valentine, born in 1957, who gained fame on the rodeo circuit. Royal Blue Boon, a famous 1980 blue roan, was the first in a line of world-class cutting horses.

Are Roan Horses Gray?

To put it simply: nope! Roans are not grays and grays are not roans. Often, though, roans are mistaken for grays. It is an understandable mistake since horses can exhibit characteristics of both colors.

What sets gray coats – a common color in nearly all breeds – apart from blue roans, though, is that a gray coat gets lighter and lighter with time. Gray horses can be born any other color and fade to gray, even if there’s no indication right away they may have a gray coat. They can even be born looking roan! But then the coat grays out.

Gray roan horse grazing on pasture

Adult grays can grow up to keep none of their original coat color – or even have a “white” looking coat, but their eye and skin colors remain unchanged.

A gray coat will first begin to show around the eyes and the muzzle. While the coats grays outs further, it can often have a roan-like appearance in the middle of the process, leading to that mistake in perception.

Roans, on the other hand, do not have a graying gene to enable them to grow more white hair as they age.

Final Thoughts

Blue roans are beautiful horses. The fact that they are a bit of an optical illusion of white on black, too, just makes them all the more special. True blue roans are black horses with the roan gene. It is this combination of pure white on solid black that sets them apart and makes them one of the most highly desirable roan varieties.