Each horse has a basic colour, which can be black, bay/brown or chestnut. Estos colores básicos de la capa son controlados por los genes Extension y Agouti. El gen de extensión (E-locus) controla la producción de pigmento negro y rojo. La prueba de Color Castaño (P904) analiza el estado genético del gen Extensión. El gen de la extensión tiene dos variantes (alelos). El alelo dominante E produce pigmento negro y el alelo recesivo e produce pigmento rojo. Todos los caballos, independientemente del color de su pelaje, tienen la genética del pigmento negro o rojo. Los caballos rojos (por ejemplo, castaño, acedera, palomino y cremello) tienen dos copias del alelo recesivo e, también llamado eo homocigoto. Los caballos pigmentados en negro (por ejemplo, negro, marrón, marrón, negro ahumado, piel de ante, crema ahumada y perlino) tienen al menos una copia del alelo E. Pueden ser homocigotos EE o heterocigotos Ee.
The Coat Colour Chestnut test encloses the following results, in this scheme the results of the Coat Colour Chestnut test are shown in combination with the possible results for the Coat Colour Agouti test:
|
Result Chestnut |
Result Agouti |
Coat Colour |
Descripción |
|---|---|---|---|
|
e/e |
A/A, A/a or a/a |
Chestnut, Sorrel |
Only the recessive allele e was detected, the horse is homozygous for red pigment (ee). The basic colour is chestnut or sorrel unless modified by other colour modifying genes. It can only pass on allele e to its offspring. |
|
E/e |
a/a |
Black |
The horse is heterozygous for red pigment (Ee). The basic colour is black unless modified by other colour modifying genes. It can pass on either allele E or e to its offspring. |
|
E/e |
A/A or A/a |
Bay, Brown |
The horse is heterozygous for red pigment (Ee). The basic colour is bay or brown unless modified by other colour modifying genes. It can pass on either allele E or e to its offspring. |
|
E/E |
a/a |
Black |
Only the dominant allele E was detected, the horse is homozygous for black pigment (EE). The basic colour is black unless modified by other colour modifying genes. It can only pass on allele E to its offspring and therefore cannot produce red foals. |
|
E/E |
A/A or A/a
|
Bay, Brown |
Only the dominant allele E was detected, the horse is homozygous for black pigment (EE). The basic colour is bay or brown unless modified by other colour modifying genes. It can only pass on allele E to its offspring and therefore cannot produce red foals. |