~~~ The Black Arabian Allure ~~~ (and where does the black come from?)
“The nearly universal fascination with black Arabians is well illustrated by a story concerning the famous Egyptian breeder Prince Mohamed Aly (breeder of *Fadl, *Maroufa, *Zarife, *Roda, *Aziza, etc.). He was so anxious to have black foals that he had the blackest cloth he could find, draped in the stalls of his expectant broodmares to induce the fates to smiles and give him black foals. He also used the liver chestnut stallion Ibn Rabdan extensively in his breeding program to obtain the rare and elusive black color.

Still a challenge...
“Prince Mohamed Aly’s superstitious puzzlement about black color genetics reflects the difficulties facing those who want to produce the color in America today. But no matter what the bloodline, breeders everywhere breathe a little faster when they see a mousy gray foal lying in the straw of a foaling stall, because they know that the baby will grow up to be the treasured ebony color so sought after worldwide.”

(EXCERPT FROM BLACK ARABIANS, ARLENE MAGID, AHT 03/96)

Black vs. Chestnut ~~~
The basic gene that controls color of horses is called the ‘E’ gene. It is the one responsible for the main body color. There are really only two basic body colors, black and chestnut. Of course there are many other genes that if present, can interact with the basic black or chestnut, thus creating an infinite variety of horse colors and coat patterns.

But getting back to the basic body color gene, the two possibilities are black, known as the large ‘E’ gene because it is dominant over the chestnut gene, which is known as small ‘e’. Every foal receives a pair of these genes, one from each parent. If it receives the 'E' (black) gene from both parents, it will have the combination of ‘EE’ and will display the black color. But if it receives the 'e' (chestnut) gene from both parents, it will have the combination of ‘ee’ and will display the chestnut color. When this happens, where a foal receives a ‘matched set’ or matching genes from both parents, it is referred to as ‘homozygous’.

However, if it receives the E (black) gene from one parent, but the e (chestnut) gene from the other parent, it will have the combination of ‘Ee’. This foal has received a ‘mixed set’ of genes and is referred to as being ‘heterozygous’ for that gene. In this case, both genes are present, but since the black ‘E’ is dominant over the chestnut ‘e’ gene, the foal will display the black coat color, but can still pass on EITHER color gene to its offspring later.

It follows then, that all horses having at least one large ‘E’ gene will display the black color, and therefore if a horse displays the chestnut color, it must always have the ‘ee’ combination. That is why black horses can be either homozygous ‘EE’ or heterozygous ‘Ee’. And that is why crossing a chestnut ‘ee’ with a chestnut ‘ee’ will always produce a chestnut, because the foal can only receive the ‘e’ gene from both parents and thus be chestnut ‘ee’ itself.

Bays ~~~
But what about bays? The bay color is caused by a whole different gene called the ‘A’ (or agouti) gene which acts to modify the basic coat colors we described above. Basically, when the large ‘A’ (dominant) form of this modifier is present in the ‘EE’ or ‘Ee’ (black) colored horse, it modifies the body color to a reddish color, thereby restricting the black color to the extremities—legs, ear tips, mane, and tail— thus creating the bay color. However, when the small ‘a’ (recessive) version of the gene is present, there is no modification or restriction of coat color. In other words, the small ‘a’ appears inactive, as if it’s absent, thus allowing the basic body color of black (or chestnut) to be displayed evenly over the entire body, without any restriction or modification.

There are also more than just the two possibilities for this gene – ‘A’ and ‘a’. There is a whole range of A genes such as ‘A+, A, a+, a’ which range in dominance from most dominant ‘A+’ (greatest color restriction, light bay) to the least dominant ‘a’ (inactive, no restriction, solid black or chestnut), with the ones in between causing some modification towards bay coloring, but still allowing some of the basic color hairs to show as well, such as in the black-bay. This is why there are so many different varieties and shades of bay. For example, a foal that receives (one from each parent) a matched set of ‘AA’ genes might be a bright bay, and the foal that receives a mixed set of ‘Aa+’ or ‘a+a’ might be a mahogany-bay or black-bay. But the foal that receives a matched set of ‘aa’ will not have any apparent bay coloring and instead will have its basic body color of black or chestnut displayed evenly over the entire body.

Since the large ‘A’ (bay) gene acts to modify the body color to a reddish color while leaving the extremities alone, it is definitely more noticeable on the ‘EE’ or ‘Ee’ (black) colored horse. On the ‘ee’ (chestnut) horse it is difficult to tell if the dominant ‘A’ or recessive ‘a’ gene is present, because the coat color is still a reddish color either way. Some say the ‘A’ gene in a chestnut can result in a brighter, redder chestnut color. But any horse, bay or chestnut, that carries at least one large ‘A’ (bay-causing) gene, can pass it on to its offspring thereby producing a possible bay. And any horse, bay or chestnut, that carries at least one small ‘a’ gene (the inactive version), can pass it on to its offspring thereby producing solid or ‘non-bay’ coloring.

Grays ~~~
The ‘gray’ gene is another gene that acts as a modifier to change the basic coat color. But the gray ‘G’ gene is different because it is a progressive gene, often not noticeable at birth, but causing progessive graying as the horse ages. Here again, the large ‘G’ is dominant and will always eventually produce the gray coloring. When the small ‘g’ (recessive, no-graying) version of the gene is present, it appears to be inactive, as if it’s absent, thus allowing the basic body color to be displayed without any eventual graying.

Remember, when all foals are born, they have one of the basic body colors as described above, black or chestnut, (or bay if they have the large ‘A’). Whether they will eventually turn gray depends on if they received a large ‘G’ or small ‘g’ from their parents. Every foal receives a pair of these genes, one from each parent. If it receives the ‘G’ (graying) gene from both parents, it will have the combination of ‘GG’ and will eventually display the progessive graying. But if it receives the ‘g’ (inactive, no-graying) gene from both parents, it will have the combination of ‘gg’ and will NOT have any eventual graying, and instead will keep its basic body color throughout its lifetime.

Here again, if it receives the ‘G’ (graying) gene from one parent, but the ‘g’ (inactive, no-graying) gene from the other parent, it will have the combination of ‘Gg’. This foal has received that ‘mixed set’ of genes and is ‘heterozygous’ for that gene. In this case, both genes are present, but since the gray-causing ‘G’ is dominant over the inactive ‘g’ gene, the foal WILL eventually display the graying coat color, but can still pass on EITHER gene to its offspring later. (Also remember, that if a parent carries a large ‘G’ gene to pass on to its offspring, it will always be a gray horse itself, since it has the dominant ‘G’ gene itself. That is why every gray foal must have at least one gray parent.)

Pintos and Paints ~~~
Pinto spotted coloring is caused by still other genes, the Tobiano pattern being caused by the ‘T’ gene and the Overo by the ‘O’ gene, and the Tovero by a mixture of the two. The Overo spotting pattern involves more complex inheritance rules, since the simple dominance doesn’t apply and recessive genes are required for spotting to occur, making the Overo sometimes unpredictable.

The Tobiano pattern is caused by the dominant ‘T’ gene in a manner similar to the ‘G’ graying gene, except that it is not a progressive gene, but instead is apparent at birth. Once again, every foal receives a pair of these genes, either ‘T’ or ‘t’, one from each parent. The large ‘T’ is dominant (exhibits spotting), the recessive ‘t’ version is inactive (solid body color, no spotting). If it receives the ‘T’ (spotting) gene from either or both parents, having either the combination of ‘TT’ or ‘Tt’, it will display the spotted color pattern. But if it receives the ‘t’ (inactive, no-spotting) gene from both parents, it will have the combination of ‘tt’ and will display solid body color, no spots. Thus once again, every Tobiano-spotted foal must have at least one Tobiano-spotted parent.

The dominant ‘T’ gene (spotted version) is not found in purebred Arabians, as all purebred Arabians carry a matched set of ‘tt’genes (solid, non-spotted). The dominant ‘T’ Tobiano gene (spotted version) may be found in half-Arabians though, as a result of crossing with other breeds that carry the large ‘T’ gene, such as Pintos, Paints, some Saddlebreds, etc.

Still more genes are responsible for other colors such as roan, dun, buckskin, palomino, appaloosa, and so on and on and on. There are countless combinations of color genes, and many factors influencing color are not yet fully understood, with experts revising their opinions continually. This is certainly not intended as a detailed discussion on genetics, but merely a simple summary of some basic concepts for any average person interested in “where the colors come from.” Anyone with comments, ideas, or questions about possible outcomes from a given cross, feel free to email me. It is an interesting topic, and one I always enjoy discussing. Send email to Karen at sunfirearabians@hotmail.com

Conclusion ~~~
Bottom line—There are just two rules of breeding for coat color that ALWAYS apply:
~~~~~~ 1. Chestnut to chestnut always produces chestnut!
~~~~~~ 2. Rule #1 is the only rule!

Black to black does not always produce black nor does bay to bay always produce bay. Two black parents can pair up two recessive chestnut genes and produce a chestnut. Two bay parents can pair up two recessive ‘a’ genes and produce a black or pass on recessive ‘e’ genes and produce chestnut. Even black to chestnut can sometimes produce bay. Early teachings of the Bedouins demonstrated that each color of the horse was valued in a distinct way—the ceremonial gray, the fleet chestnut, the sure-footed bay, and the black horse described as “the bearer of great fortune.” Reserved for sheiks and rulers, the black horse was a gift of supreme value and given only to the most respected of leaders.

But no matter the color, the classic beauty of the Arabian is undeniable.
“Like an exquisite gem nestled in a velvet box,
it is the heart, mind and soul of an Arabian horse
which lies beneath his glorious coat that truly makes him a treasure.”