GeneticsBook-qh masci.pdf

Color Coat Genetics

AMERICAN ²UARTER HORSE

Sorrel

Chestnut

Bay

Brown

Black

Palomino

Buckskin

Cremello

Perlino

Red Dun

Dun

Grullo

Red Roan

Bay Roan

Blue Roan

Gray

SORREL

WHAT ARE THE COLOR GENETICS OF A SORREL?

Like CHESTNUT, a SORREL carries TWO copies of the RED gene only (or rather, non-BLACK)

meaning it allows for the color RED only. SORREL possesses no other color genes, including BLACK,

regardless of parentage. It is completely recessive to all other coat colors. When breeding with a

SORREL, any color other than SORREL will come exclusively from the other parent. A SORREL or

CHESTNUT bred to a SORREL or CHESTNUT will yield SORREL or CHESTNUT 100 percent of

the time. SORREL and CHESTNUT are the most common colors in American Quarter Horses.

WHAT DOES A SORREL LOOK LIKE?

The most common appearance of SORREL is a red body with a red mane and tail with no black

points. But the SORREL can have variations of both body color and mane and tail color, both areas

having a base of red. The mature body may be a bright red, deep red, or a darker red appearing almost

as CHESTNUT, and any variation in between. The mane and tail are usually the same color as the

body but may be blonde or flaxen. In fact, a light SORREL with a blonde or flaxen mane and tail may

closely resemble (and is often confused with) a PALOMINO, and if a dorsal stripe is present (which a

SORREL may have), it may be confused with a RED DUN.

IF A SORREL HORSE HAS A DORSAL STRIPE, DOESN’T THAT MAKE IT A DUN?

Foals that will be SORREL are often born with light red hair coloration as well as having a distinct dorsal stripe. This characteristic is often confused with and mistaken as

RED DUN. However, a SORREL is a non-diluted horse. A dorsal stripe can be inherited from a non-DUN parent. A SORREL foal usually loses the dorsal stripe upon

shedding its first coat. But even if the SORREL retains the dorsal stripe as a mature horse, it still is not due to the DUN DILUTION gene. One may notice that the mature

coat of the SORREL does not include zebra stripes on the legs.

IF A RED OR SORREL COLORED HORSE HAS A BLACK MANE AND TAIL, DOESN’T THAT MAKE IT A BAY?

A BAY must have black on ALL points. Not only are the mane and tail black but also the tips of the ears and the lower legs from the coronet up. Oftentimes, a horse with a

RED or SORREL body color will also have a very dark mane and tail that is often confused with black. However, the mane and tail are dark due to concentrated amounts of the

RED pigment, giving them the appearance of black against the brighter RED coat color. One may notice that these horses do not have black tips on the ears nor is there black

on the lower legs. This color is registered as CHESTNUT.

WHAT ARE SOME OTHER ASPECTS WE NEED TO KNOW ABOUT SORREL?

Referring to the color of a horse as SORREL is common throughout the West. However, this color historically is referred to as CHESTNUT.

It is possible for SORREL to express the roan gene. AQHA recognizes this color as RED ROAN. (See RED ROAN)

A SORREL may have white hair scattered throughout the body or have white hair concentrated in specific areas. It is most often confused with ROAN but is neither the result

of the ROAN nor GRAY genes. These areas are usually the flanks, between the fore legs, the root of the tail (usually in bands similar to that of a raccoon–hence, ‘coon-tail’),

and sometimes over the barrel, usually in vertical patterns directly over each rib. This distinct pattern of white is sometimes called rabicano (pronounced rab ih CON oh), a

word of Spanish origin meaning “brush tail,” referring to the bands of white hair at the root of the tail. It is also referred to sometimes as “ticking.” One way to determine the

difference between the ‘classic’ RED ROAN and a SORREL with white hair due to the rabicano or ticking trait is to notice the color of hair once the ‘roan’ areas have been

scraped or rubbed off. On a ‘classic’ ROAN, the ROAN hair does not grow back once scraped off–only the base color will grow back, in this case, SORREL. On the horse

exhibiting the rabicano trait, the hair that is scraped off will usually grow back solid white.

Some GRAY horses may have started out as SORREL. These horses may keep their RED points (or a variation) and much of their RED coat (or a variation) for an extended

period of time. These horses still retain the RED gene and may produce SORREL horses.

CHESTNUT

WHAT ARE THE COLOR GENETICS OF CHESTNUT?

Like SORREL, a CHESTNUT carries TWO copies of the RED gene only (or rather, non-BLACK)

meaning it allows for the color RED only. CHESTNUT possesses no other color genes, including

BLACK, regardless of parentage. It is completely recessive to all other coat colors. When breeding

with a CHESTNUT, any desired color other than SORREL or CHESTNUT will come exclusively

from the other parent. A SORREL or CHESTNUT bred to a SORREL or CHESTNUT will yield

SORREL or CHESTNUT 100 percent of the time.

WHAT DOES A CHESTNUT LOOK LIKE?

CHESTNUT, like SORREL, is the most common color in American Quarter Horses, both having a

base color that is solid RED, although CHESTNUT may not appear red. A mature CHESTNUT may

exhibit a deeper red with an almost ‘wine colored’ sheen. It is oftentimes a red so dark that it appears

BROWN and may be confused with ‘seal’ BROWN. (The RED FACTOR test can be performed

where such a question occurs. Contact AQHA for more information.) The mane and tail are usually

the same as the body color but may also be blonde or flaxen. In fact, a CHESTNUT with a blonde or

flaxen mane and tail may closely resemble (and is often confused with) a dark or ‘chocolate’ PALOMINO. The mane and tail may be so dark that they appear BLACK, but a

CHESTNUT will never have true black points. Like the SORREL, a CHESTNUT may also have a dorsal stripe.

IF A CHESTNUT HORSE HAS A DORSAL STRIPE, DOESN’T THAT MAKE IT A DUN?

A CHESTNUT with a dorsal stripe is not related to DUN. Remember, a CHESTNUT is a non-diluted horse. A dorsal stripe can be inherited from a non-DUN diluted parent.

Foals that will be CHESTNUT are often born with light red hair coloration as well as having a distinct dorsal stripe. This characteristic is often confused with and mistaken as

RED DUN. Quite often, a CHESTNUT foal will lose the dorsal stripe upon shedding its first coat. Even if the CHESTNUT retains the dorsal stripe, it still is not due to the

DUN DILUTION gene. One may notice that a mature CHESTNUT does not have zebra stripes on the legs.

IF A RED OR CHESTNUT COLORED HORSE HAS A BLACK MANE AND TAIL, DOESN’T THAT MAKE IT A BAY?

A BAY must have black on ALL points. Not only are the mane and tail black but also the tips of the ears and the lower legs from the coronet up. Oftentimes, a horse with a

RED or SORREL body color will also have a very dark mane and tail that is often confused with black. However, the mane and tail are dark due to concentrated amounts of the

RED pigment, giving them the appearance of black against the brighter RED coat color. One may notice that these horses do not have BLACK tips on the ears nor is there true

black on the lower legs. The CHESTNUT or SORREL colored horse with a very dark mane and tail is registered as CHESTNUT.

WHAT ARE SOME OTHER ASPECTS WE NEED TO KNOW ABOUT CHESTNUT?

It is possible for CHESTNUT to express the roan gene. AQHA recognizes this color as RED ROAN. (See RED ROAN)

A CHESTNUT may have white hair scattered throughout the body or have white hair concentrated in specific areas. These areas are usually the flanks, between the fore legs,

the root of the tail (usually in bands similar to that of a raccoon–hence, ‘coon-tail’), and sometimes over the barrel, usually in vertical patterns directly over each rib. It is most

often confused with ROAN but is neither the result of the ROAN nor GRAY genes. This distinct pattern of white is sometimes called rabicano (pronounced rab ih CON oh), a

word of Spanish origin meaning “brush tail,” referring to the bands of white hair at the root of the tail. It is also referred to sometimes as “ticking.” One way to determine the

difference between the ‘classic’ RED ROAN and a CHESTNUT with white hair due to the rabicano or ticking trait is to notice the color of hair once the ‘roan’ areas have been

scraped or rubbed off. On a ‘classic’ ROAN, the ROAN hair does not grow back once scraped off–only the base color will grow back, in this case, CHESNUT. On the rabicano

affected horse, the hair that is scraped off will usually grow back solid white, the same that would happen if the horse were a solid CHESTNUT.

Some GRAY horses may have started out as CHESTNUT. They may keep their CHESTNUT points (or a variation) and much of their CHESTNUT coat (or a variation) for an

extended period of time. These horses still retain the RED gene and may produce CHESTNUT horses.

BAY

WHAT DOES A BAY LOOK LIKE?

Basically, a BAY has a general base color that ranges anywhere from a deep tan, to copper-red (similar

to the color of SORREL), to a darker, brownish-red (similar to that of CHESTNUT). Add to this the

color black that is localized to the points (mane and tail, lower legs, tips and rims of ears). As with

other coat colors, there are variations of BAY. In addition to the RED color range of the body, a BAY

may also have black covering or counter shading over most of the body giving it a ‘sooty’ or ‘smutty’

appearance. The lighter-colored or ‘tan’ BAYS are not to be confused with BUCKSKINS, although

oftentimes they are, sometimes having very gold areas on the body. BAY, which may have a dorsal

stripe, is often confused with DUN. (See below for further explanation)

(See DUN and BUCKSKIN)

WHAT ARE THE COLOR GENETICS OF A BAY?

On a BAY, the color BLACK is distributed only to the points due to the presence of the agouti gene

(pronounced ah GOO tee). (See Agouti gene in index) When this gene is present, it tells the color

BLACK to be located at the points only. The base color is left as some variation of RED which may

include a deep, red-tinted tan that is not associated with either BUCKSKINS or DUNS. BAY must have at least one parent that is BLACK or has black points. BAY will

always carry the BLACK color gene.

Also, some BAY horses are homozygous for the agouti gene. This means that each parent of the BAY passed on one copy of this gene; thus, the foal received two copies. The

homozygous BAY will produce a foal with black points (never a solid BLACK) 100 percent of the time, regardless of the color of the other parent.

CAN A BAY HORSE PRODUCE A SOLID BLACK HORSE?

A horse that is a solid BLACK or has black points can potentially produce a solid BLACK horse. This includes the BAY. In fact, depending on the parentage, a BAY horse can

be homozygous for the BLACK gene. For this to be possible, each parent of the homozygous BAY must have black points. Both a stallion and a mare can be homozygous for the

color black. This means that the parent homozygous for the BLACK gene will always produce a foal that is either solid BLACK or has black points no matter what color the

other parent is.

IF A BAY HORSE HAS A DORSAL STRIPE, DOESN’T THAT MAKE IT A DUN?

A BAY with a dorsal stripe is not related to DUN. Remember, a BAY is a non-diluted horse–even the tan BAYS. A dorsal stripe can be inherited from a non-DUN diluted

parent. The counter shading on some BAYS may be expressed to a minimal degree, usually localized to the withers and thinner areas along the back. A BAY may also have, to

some degree, subtle shading often confused with leg-barring, usually located on the back of the fore legs. These characteristics are not to be confused with the DUN, including

the color GRULLO, and have nothing to do with the DUN gene.

WHAT ARE SOME OTHER ASPECTS WE NEED TO KNOW ABOUT BAY?

It is possible for the BAY to express the ROAN gene. Genetically, this is called a BAY ROAN. This is recognized as a separate coat color with AQHA. (See BAY ROAN)

A BAY may have white hair scattered throughout the body or have white hair concentrated in specific areas. These areas are usually the flanks, between the fore legs, the root of

the tail (usually in bands similar to that of a raccoon–hence, ‘coon-tail’), and sometimes over the barrel, usually in vertical patterns directly over each rib. It is most often

confused with ROAN but is neither the result of the ROAN nor GRAY genes. This distinct pattern of white is sometimes called rabicano (pronounced rab ih CON oh), a word

of Spanish origin meaning “brush tail,” referring to the bands of white hair at the root of the tail. It is also referred to sometimes as “ticking.” One way to determine the

difference between the ‘classic’ BAY ROAN and a BAY with white hair due to the rabicano or ticking trait is to notice the color of hair once the ‘roan’ areas have been scraped

or rubbed off. On a ‘classic’ ROAN, the ROAN hair does not grow back once scraped off–only the base color will grow back, in this case, the base color of BAY, which is

usually SORREL or CHESTNUT. On the rabicano affected horse, the hair that is scraped off will usually grow back solid white, the same that would happen if the horse were a

solid BAY.

Some GRAY horses may have started out as BAY. These horses may keep their black points and much of their red coat (or a variation) for an extended period of time. They still

retain the color genetic information to produce BAY foals regardless of the color of the other parent. (See GRAY)

BROWN

WHAT DOES A BROWN LOOK LIKE?

There is somewhat of a variation within the color BROWN. SEAL BROWN horses are consistently

dark or ‘seal colored’ over the entire body. They may or may not have distinct black points, although

almost all BROWNS do. A BROWN horse with brown colored points (not black in appearance, but

genetically still black) is often confused with CHESTNUT. (The RED FACTOR test can be performed

where such a question occurs. Contact AQHA for more information.) Some horses registered as

BROWN may actually be ‘smutty’ BAYS (See BAY), very ‘smutty’ BUCKSKINS (See BUCKSKIN),

diluted BLACK horses (See BLACK), or BLACK horses with coats that fade anywhere from a brownish

red to a brownish tan, oftentimes giving them the appearance of BAYS or dark BUCKSKINS.

CAN A BROWN HORSE PRODUCE A SOLID BLACK HORSE?

A horse that is a solid BLACK or has black points can potentially produce a solid BLACK horse. This

includes the BROWN, which must have at least one parent that is BLACK, BROWN, or a color with

black points. In fact, depending on the parentage, a BROWN horse can be homozygous for the

BLACK gene. For this to be possible, each parent of the homozygous BROWN must carry the

BLACK gene, usually having black points. Both a stallion and a mare can be homozygous for the color black. This means that the parent homozygous for the BLACK gene will

always produce a foal that is either solid black or has black points no matter what color the other parent is.

Sometimes a foal that will be BROWN is born with anything from a silvery, grayish coat to a smoky, tan-colored coat complete with a dorsal stripe. The mane and tail will be

black or dark brown. This combination of color and dorsal stripe is very commonly confused with a GRULLO. However, once the foal sheds its first coat, the dorsal stripe will

no longer be visible in most cases.

IF A BROWN HORSE HAS A DORSAL STRIPE, DOESN’T THAT MAKE IT A DUN?

A BROWN with a dorsal stripe is not related to DUN. The dorsal stripe is usually inherited from a non-DUN diluted parent. Some foals that will be mature BROWNS are

often born with characteristics which can be confused with DUNS or GRULLOS. They may have distinct dorsal stripes (which they may or may not keep after the first shed)

and some shading of darker hair over the withers. These characteristics are not related to the DUN DILUTION gene, even though are often confused with DUNS or

GRULLOS, and is considered as a type of camouflaging (much in the way that a fawn has spots on its coat) which was necessary before the horse was domesticated.

WHAT ARE SOME OTHER ASPECTS WE NEED TO KNOW ABOUT BROWN?

It is possible for the BROWN to express the ROAN gene. Usually this is considered as BLUE ROAN which is recognized as a separate coat color with AQHA. (See BLUE

ROAN)

A BROWN may have white hair scattered throughout the body or have white hair concentrated in specific areas. These areas are usually the flanks, between the fore legs, the

root of the tail (usually in bands similar to that of a raccoon–hence, ‘coon-tail’), and sometimes over the barrel, usually in vertical patterns directly over each rib. It is most often

confused with ROAN but is neither the result of the ROAN nor GRAY genes. This distinct pattern of white is sometimes called rabicano (pronounced rab ih CON oh), a

word of Spanish origin meaning “brush tail,” referring to the bands of white hair at the root of the tail. It is also referred to sometimes as “ticking.” One way to determine the

difference between the ‘classic’ BLUE ROAN and a BROWN with white hair due to the rabicano or ticking trait is to notice the color of hair once the ‘roan’ areas have been

scraped or rubbed off. On a ‘classic’ ROAN, the ROAN hair does not grow back once scraped off–only the base color of the body will grow back. On the rabicano affected

horse, the hair that is scraped off will usually grow back solid white, the same that would happen if the horse was a solid BROWN.

Some BROWNS have a PALOMINO or BUCKSKIN parent. In many cases, these BROWNS will also carry the CREAM DILUTION inherited from one of these parents.

These BROWNS will then have the color genetics similar to BUCKSKINS and can produce any of the DOUBLE DILUTE foals if bred to a PALOMINO, BUCKSKIN, or

parent known to carry the CREAM DILUTION. BROWNS carrying the CREAM DILUTION may develop dappling on the coat if they are left in the sun for lengthy periods

of time.

Some GRAY horses may have started out as BROWN. These horses may keep their black points and much of their BROWN coat (or a variation) for an extended period of

time. They still retain the color genetic information to produce BROWN foals as well as many other colors, depending on the pedigree, regardless of the color of the other

parent. (See GRAY)

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