Sorrel horse color

What Color is a Sorrel Horse?

For both long-time and beginner equestrians, the aspect of horse colors can be confusing at times. This fact holds particularly true when discussing sorrel horses but what color is a sorrel horse?

The confusion, in this case, comes about because a significant portion of the equestrian community deems chestnut to be the same as sorrel.

Sorrel-colored horses are observed to have a pure shade of bright red similar to copper which occurs throughout its entire body.

Chestnut, on the other hand, is argued by others to similarly be a pure shade of red, but with a dark brown hue undertone to it.

Other experts argue that sorrel is simply a lighter shade of chestnut. Are you feeling a little confused as to which version of these is fact yourself? Not to worry!

To get a better understanding of what color sorrel is, we’re going to discuss some details concerning horse colors in this post and get to the bottom of answering what color sorrel horses truly are.

A Look at the Science behind Coat Colors

Before talking more about the color of a sorrel horse, it’s prudent we first understand a little of the biology behind coat colors. This explanation will help you understand how different coat colors arise. Buckle in for a short science lesson!

Firstly off, you should know that there are 3 basic coat colors for horses. They are black, bay, and chestnut/sorrel (In several equine circles, chestnut and sorrel are used interchangeably.)

For all these colors, two genes have to interact to create them. They are the ASIP gene and the MC1R gene.

Before diving into what MC1R and ASIP are, let’s explain a few key terminologies:

Genes: These comprise DNA and carry the information that determines an offspring’s characteristics.

Allele: These are variations of a gene.

Dominant allele: These show their effect despite an offspring having only one copy of it.

Recessive allele: These show their effect only if an offspring has both copies of it.

Remember that an offspring receives genes from two sources (male and female). That’s where the point of having only one or both copies of an allele comes in.

Explaining the Genes


MC1R stands for Melanocortin 1 Receptor. In mammals, it’s heavily involved in controlling their skin and hair color. In horses, it regulates the production of red and black pigments.

Currently, studies into MC1R in horses have led to the discovery of three alleles, namely E, e, and ea. The e and ea alleles are recessive to the E allele.


ASIP stands for Agouti Signaling Protein. It’s also simply referred to as Agouti. In mammals, it’s responsible for dispensing melanin pigments.

When it comes to horses, in particular, this gene is responsible for allocating the black pigment. Two alleles, A (dominant) and a (recessive) have been identified for this gene.

The dominant A allele controls the placement of the black pigment to specific parts of the horse such as the mane. On the other hand, the recessive a allele allows the black pigmentation to be evenly spread on the horse’s entire body.

How it Works for Red Colored Horses

Based on what we’ve discussed above, we can now move on to see how sorrel-colored horses come about.

The gene responsible for giving a sorrel horse their red color is either the recessive e or ea. In other scientific terms, they are referred to as the red factor.

What that means is that for a sorrel horse color to be born, the offspring has to receive a combination of either 2 e alleles or 2 ea alleles. This fact also implies that a sorrel horse can only be gotten when both parents are also similarly colored red.

Should the dominant E allele be present in a horse, however, then black pigmentation would be observed on the hair around places like its tail or mane.

From the Genetic Perspective

Looking at historical texts that documented the study of horse colors, one of them claimed to observe differences between sorrel and chestnut-colored horses on a genetic level.

While it may have gotten people talking for a while, modern science has since proven these observations wrong.

Sorrel and chestnut are the same color genetically! It’s certain that this fact is a major reason behind the never-ending debate on trying to differentiate between sorrel-colored horses and chestnuts.

So, until another scientific discovery manages to tell us differently, it seems equestrians who are for the cause that these two colors are the same are winning the discussion.

Sorrel vs. Chestnut Debate

Science may have had its say on the matter, but equestrians have their opinion as well.

A significant portion of equestrians claims, no, swear by the fact that there truly is a difference between sorrel and chestnut-colored horses.

Considering that many of them have lived in the equestrian sphere, working with and observing horses virtually all their lives, their opinions aren’t to be brushed aside quite so simply.

Their stance remains that sorrel-colored horses have a copper-reddish color. They absolutely have no hint of black on any part of the horse. The color on the mane and tail also match the overall body color.

Chestnut, on the other hand, is distinct to them in that it still has the same red base as sorrel. The shade is darker, almost approaching a dark brown hue. For these horses, the color on the mane and tail could be uniform to the overall body color or appear a shade lighter.

What Professional Equestrian Bodies Say

The issue of defining a sorrel-colored horse is an issue of debate as well in pro-equestrian circles.

For one thing, some claims about the inconsistency in agreeing that there’s a difference between sorrel and chestnut-colored horses arise from a difference in location.

In some parts of the world, the color sorrel isn’t recognized officially by all equestrian bodies. This means that most horse registrations are done with chestnut recorded as the official color of the horse despite what the owner may personally think.

In other parts of the world like in the UK, using sorrel is widely accepted.

Some bodies also have strict regulations concerning the type or breed of horse. This heavily plays into the decision on whether to allow the registration of a horse as a sorrel.

Following the seemingly never-ending debate on how to distinguish these two colors. Some pro bodies have both options available for registering horses. They do so as a means to also sort out horses that don’t fall under the bay color spectrum.

The Origins of Sorrel

The sorrel aspect of horse colors is actually a borrowed term. Sorrel is a type of small, green herb that has been part of human cuisine for a long time.

While the sorrel herb is green, the veins and stem have a dark red color to them. The word sorrel has been in use since the late 14th century, originating in France.

Since then, the word has spread across the world. It has become synonymous with a specific color observed in several varieties of horses. This term is especially popularly used in the USA to describe most of the red-colored horses.

A Brief History of Horse Colors

Before the domestication of horses thousands of years ago, wild horses had coats that were observed as being light brown. The color had a tinge of yellow to it as well. The mane had a darker shade compared to the coat.

This color composition was important to them since it allowed them to camouflage in their environment.

Horses are herbivores, and if you recall your biology, that means they only eat vegetation. This characteristic of horses implies that they are animals targeted as prey by carnivorous animals. That’s why the camouflage was integral to their survival.

When domestication began, horses from different areas which had lived and survived under different conditions were bred to create new breeds.

(Environmental factors such as exposure to different weather elements have been discovered to play a part in determining the horse coat colors.)

From historical records dating as far back as 5 BC, this crossbreeding allowed red and black colored horses to emerge.

Later around 3 BC as crossbreeding continued, newer coats emerged, much more diverse than the first two.

That’s how we have a wide variety of horse colors in the equestrian world today.

A Quick Fun Fact

Horse racing is one of the most popular equine sports the world over and with good reason. The intensity of the race, the skill involved, the training behind both the horse and jockey all come together to produce a harmonious performance.

To see horses competing at their maximum potential is simply a thing of beauty.

On that note, the best racing horse of all time was a thoroughbred sorrel! He was a beautiful horse named Secretariat, whose performances on the track remain legendary to this day.

He managed to set many records on the track as well as winning several accolades, forever immortalizing his name in horse racing history.

A Final Word

We have highlighted several aspects regarding the topic of what color sorrel horses are. The fact is they are red-colored.

The point on whether or not sorrel is the same as chestnut, or a shade of it however remains a contentious issue for the entire equestrian community, but at the end of the day, both points of view seem valid.

It doesn’t change the fact that these horses are beautiful and magnificent beasts!