Smoky black
Encyclopedia
Smoky black is a hair coat color
of horse
s in which the coat is either black or a few shades lighter than true black. Smoky black is produced by the action of a heterozygous (single copy) cream gene
on an underlying black
coat color. Therefore, smoky black is a member of the cream
family of coat color dilutions
, and found in horse populations that have other cream gene-based colors such as palomino
, buckskin, perlino
and cremello
. All smoky blacks must have at least one parent with the cream gene, and a smoky black can be verified through DNA
testing. Smoky black has been mistaken for faded black
, dark bay or brown
, grullo
or even liver chestnut
.
A smoky black horse usually appears to be a black
horse and the dilution gene
dilution factor is not visible. However, the coat may be somewhat more prone to fade to a brown shade if weathered or sun-bleached. Conversely, just because a black horse may fade in the sun does not necessarily prove or disprove that it is a smoky black.
Two copies of the cream gene on a black base coat produce a smoky cream, a cream-colored horse which is visually difficult to distinguish from a perlino or cremello, but can be identified through DNA testing.
Smoky black foal
s must always have at least one parent with the cream dilute
gene and at least one parent that carries the "E" extension gene associated with black
coloring. This could occur one of two ways: A foal could have a smoky black parent or a buckskin parent carrying both genes within a single horse. A smoky black could also be produced by breeding one horse with only the cream dilution, such as a palomino
, to a bay or black horse carrying only the extension gene, but no cream dilution. As foals, smoky blacks are typically quite silvery, and may be mistaken for grullo
s, especially when born with primitive countershading
. Smoky black foals are sometimes born with reddish tufts of hair in their ears. However, both traits are also seen in many true black foals as well.
While it superficially resembles other coat colors, experienced horse persons often detect something "off" about the coat of an adult smoky black. The darkest shades among smoky blacks are almost indistinguishable from true black
but for a slightly burnished look often chalked up to sun bleaching. The palest can be mistaken for dull bays or liver chestnuts, especially if exposed to the elements. Smoky black coats tend to react strongly to sun and sweat, and many smoky blacks turn to a chocolate color with particularly reddish mane
s and tails. Bleaching due to the elements means that the legs retain their color better, and can take on an appearance of having dark points like a bay horse. Smoky blacks, however, will lack rich red tones in the coat, instead favoring chocolate and orange tones.
One way to visually identify some smoky blacks are by the eyes, which may be amber even at adulthood. However, it is sometimes difficult to distinguish an amber-brown eye from an ordinary dark brown eye unless there are other horses available for direct comparison.
horses heterozygous for the cream gene
. The mutation
that produces the cream colors is on the MATP gene on equine chromosome 21 (ECA21), and is an incomplete dominant
trait. Incomplete dominant traits differ from recessive traits
, which are only "visible" in the homozygous state, and simple dominant traits, which are just as "visible" in the homozygous or heterozygous state. Instead, the MATP mutation is visible the heterozygous state, but more so in the homozygous state. The difficulty in identifying smoky blacks has led some to describe black as "masking" cream, however smoky blacks are more properly termed "cryptic creams."
The location of the cream gene was published in 2003 and there now exists a DNA
test for the cream gene
. This test enables breeders to identify cryptic creams such as smoky blacks, dark palominos and buckskins, and creams whose coats are obscured by the action of the gray gene
or pattern genes such as pinto
.
Equine coat color
Horses exhibit a diverse array of coat colors and distinctive markings. A specialized vocabulary has evolved to describe them.While most horses remain the same color throughout life, a few, over the course of several years, will develop a different coat color from that with which they were born...
of horse
Horse
The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...
s in which the coat is either black or a few shades lighter than true black. Smoky black is produced by the action of a heterozygous (single copy) cream gene
Cream gene
The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
on an underlying black
Black (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
coat color. Therefore, smoky black is a member of the cream
Cream gene
The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
family of coat color dilutions
Dilution gene
Dilution gene is a popular term for any one of a number of genes that act to create a lighter coat color in living creatures. There are many examples of such genes:-General:...
, and found in horse populations that have other cream gene-based colors such as palomino
Palomino
Palomino is a coat color in horses, consisting of a gold coat and white mane and tail. Genetically, the palomino color is created by a single allele of a dilution gene called the cream gene working on a "red" base coat...
, buckskin, perlino
Cream gene
The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
and cremello
Cream gene
The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
. All smoky blacks must have at least one parent with the cream gene, and a smoky black can be verified through DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
testing. Smoky black has been mistaken for faded black
Black (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
, dark bay or brown
Seal brown (horse)
Seal brown is a hair coat color of horses characterized by a near-black body color; with black points, the mane, tail and legs; but also reddish or tan areas around the eyes, muzzle, behind the elbow and in front of the stifle...
, grullo
Grullo
Grullo is a color of horses in the dun family, characterized by tan-gray or mouse-colored hairs on the body, often with shoulder and dorsal stripes and black barring on the lower legs. In this coloration each individual hair is mouse-colored, unlike a roan which is composed of a mixture of dark and...
or even liver chestnut
Chestnut (coat)
Chestnut is a hair coat color of horses consisting of a reddish-to-brown coat with a mane and tail the same or lighter in color than the coat. Genetically and visually, chestnut is characterized by the absolute absence of true black hairs...
.
A smoky black horse usually appears to be a black
Black (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
horse and the dilution gene
Dilution gene
Dilution gene is a popular term for any one of a number of genes that act to create a lighter coat color in living creatures. There are many examples of such genes:-General:...
dilution factor is not visible. However, the coat may be somewhat more prone to fade to a brown shade if weathered or sun-bleached. Conversely, just because a black horse may fade in the sun does not necessarily prove or disprove that it is a smoky black.
Two copies of the cream gene on a black base coat produce a smoky cream, a cream-colored horse which is visually difficult to distinguish from a perlino or cremello, but can be identified through DNA testing.
Identification
Foal
A foal is an equine, particularly a horse, that is one year old or younger. More specific terms are colt for a male foal and filly for a female foal, but these terms are used until the horse is age three or four. When the foal is nursing from its dam , it may also be called a suckling...
s must always have at least one parent with the cream dilute
Cream gene
The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
gene and at least one parent that carries the "E" extension gene associated with black
Black (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
coloring. This could occur one of two ways: A foal could have a smoky black parent or a buckskin parent carrying both genes within a single horse. A smoky black could also be produced by breeding one horse with only the cream dilution, such as a palomino
Palomino
Palomino is a coat color in horses, consisting of a gold coat and white mane and tail. Genetically, the palomino color is created by a single allele of a dilution gene called the cream gene working on a "red" base coat...
, to a bay or black horse carrying only the extension gene, but no cream dilution. As foals, smoky blacks are typically quite silvery, and may be mistaken for grullo
Grullo
Grullo is a color of horses in the dun family, characterized by tan-gray or mouse-colored hairs on the body, often with shoulder and dorsal stripes and black barring on the lower legs. In this coloration each individual hair is mouse-colored, unlike a roan which is composed of a mixture of dark and...
s, especially when born with primitive countershading
Countershading
Countershading, or Thayer's Law, is a form of camouflage. Countershading, in which an animal’s pigmentation is darker dorsally, is often thought to have an adaptive effect of reducing conspicuous shadows cast on the ventral region of an animal’s body...
. Smoky black foals are sometimes born with reddish tufts of hair in their ears. However, both traits are also seen in many true black foals as well.
While it superficially resembles other coat colors, experienced horse persons often detect something "off" about the coat of an adult smoky black. The darkest shades among smoky blacks are almost indistinguishable from true black
Black (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
but for a slightly burnished look often chalked up to sun bleaching. The palest can be mistaken for dull bays or liver chestnuts, especially if exposed to the elements. Smoky black coats tend to react strongly to sun and sweat, and many smoky blacks turn to a chocolate color with particularly reddish mane
Mane
- Biology :* mane of a horse, the line of hair along the spine of the neck* mane of a lion, found around the male mammal's neck- Places :* Mane Department, a department in the Sanmatenga Province of Burkina Faso* French communes:...
s and tails. Bleaching due to the elements means that the legs retain their color better, and can take on an appearance of having dark points like a bay horse. Smoky blacks, however, will lack rich red tones in the coat, instead favoring chocolate and orange tones.
One way to visually identify some smoky blacks are by the eyes, which may be amber even at adulthood. However, it is sometimes difficult to distinguish an amber-brown eye from an ordinary dark brown eye unless there are other horses available for direct comparison.
Smoky black mimics
- Dark bay: When smoky blacks fade from exposure to the elements, their legs usually retain their color, giving them the appearance of a bay or brown horse with black points. However, the brown coat of a bleached smoky black recalls orange rather than red or mahogany.
- BlackBlack (horse)Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
: A true genetic black horse may still develop a sun-bleached coat, usually due to issues related to management and nutrition, though in some cases there may also be genetic factors contributing. A smoky black looks very similar to a sun-bleached black, and often only pedigree analysis or genetic testing can distinguish between the two. - Seal brownSeal brown (horse)Seal brown is a hair coat color of horses characterized by a near-black body color; with black points, the mane, tail and legs; but also reddish or tan areas around the eyes, muzzle, behind the elbow and in front of the stifle...
: The just off-black coat color of true seal browns can sometimes be misidentified as smoky black, or vice versa. - Liver chestnutChestnut (coat)Chestnut is a hair coat color of horses consisting of a reddish-to-brown coat with a mane and tail the same or lighter in color than the coat. Genetically and visually, chestnut is characterized by the absolute absence of true black hairs...
: The palest, most evenly-bleached smoky blacks may mimic the darkest shades of chestnut. Chestnuts do not have true black tones in their coats, and will usually reveal reddish character around the fetlocks. Smoky blacks usually have uniformly black legs. Furthermore, chestnuts do not possess amber eyes. - Classic champagneChampagne geneThe champagne gene is a simple dominant allele responsible for a number of rare horse coat colors. The most distinctive traits of horses with the champagne gene are the hazel eyes and pinkish, freckled skin, which are bright blue and bright pink at birth, respectively...
: Paler smoky blacks with amber eyes may be confused with the activity of champagneChampagne geneThe champagne gene is a simple dominant allele responsible for a number of rare horse coat colors. The most distinctive traits of horses with the champagne gene are the hazel eyes and pinkish, freckled skin, which are bright blue and bright pink at birth, respectively...
on a black coat. Champagne horses have pinkish, freckled skin and green, hazel or amber eyes, as opposed to the dark skin and brown or amber eyes of a smoky black. - GrulloGrulloGrullo is a color of horses in the dun family, characterized by tan-gray or mouse-colored hairs on the body, often with shoulder and dorsal stripes and black barring on the lower legs. In this coloration each individual hair is mouse-colored, unlike a roan which is composed of a mixture of dark and...
: Grullo is the action of the dun gene on black. Typically, grullo coats have cool slate hues as opposed to warm orange-brown tones. Furthermore, grullos have dun characteristics such as bold dorsal stripes and leg bars.
Genetic identification
Genetically, smoky blacks are blackBlack (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and novices frequently mistake dark chestnuts or bays for black. However, some breeds of horses, such as the Friesian horse, Murgese and Ariegeois are almost exclusively black...
horses heterozygous for the cream gene
Cream gene
The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
. The mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...
that produces the cream colors is on the MATP gene on equine chromosome 21 (ECA21), and is an incomplete dominant
Dominance relationship
Dominance in genetics is a relationship between two variant forms of a single gene, in which one allele masks the effect of the other in influencing some trait. In the simplest case, if a gene exists in two allelic forms , three combinations of alleles are possible: AA, AB, and BB...
trait. Incomplete dominant traits differ from recessive traits
Dominance relationship
Dominance in genetics is a relationship between two variant forms of a single gene, in which one allele masks the effect of the other in influencing some trait. In the simplest case, if a gene exists in two allelic forms , three combinations of alleles are possible: AA, AB, and BB...
, which are only "visible" in the homozygous state, and simple dominant traits, which are just as "visible" in the homozygous or heterozygous state. Instead, the MATP mutation is visible the heterozygous state, but more so in the homozygous state. The difficulty in identifying smoky blacks has led some to describe black as "masking" cream, however smoky blacks are more properly termed "cryptic creams."
The location of the cream gene was published in 2003 and there now exists a DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
test for the cream gene
Cream gene
The cream gene is responsible for a number of horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut will become palomino if they are heterozygous, having one copy of the cream gene, or cremello, if they are homozygous. Similarly, horses with a bay...
. This test enables breeders to identify cryptic creams such as smoky blacks, dark palominos and buckskins, and creams whose coats are obscured by the action of the gray gene
Gray (horse)
Gray or grey is a coat color of horses characterized by progressive silvering of the colored hairs of the coat. Most gray horses have black skin and dark eyes; unlike many depigmentation genes, gray does not affect skin or eye color Their adult hair coat is white, dappled, or white intermingled...
or pattern genes such as pinto
Pinto horse
A pinto horse has a coat color that consists of large patches of white and any other color. The distinction between "pinto" and "solid" can be tenuous, as so-called "solid" horses frequently have areas of white hair. Various cultures throughout history appear to have selectively bred for pinto...
.