Coat color is important to the horse lover who is breeding companion animals. Because coat color is a phenotypic genetic trait it can be used to follow inheritance from generation to generation.
Owners and breeders of horses have long been interested in the subject of coat color. A horses color patterns can make it look especially beautiful and therefore highly desired.
Some miniature horse breeders particularly treasure the palomino spotted coloration which increase the value to potential buyers, even though coat color has nothing to do with performance, health or conformation qualities. It can, however, be a predictor of parentage.
It is believed that early horses had a black based pattern and that other colors evolved in time.
Scientific Facts
The colors of the coats of horses are controlled by the genes at 12 different loci. Basic colors are black, bay, chestnut and these appear to derive from the actions of genes at agouti and extension loci.
The collection of colors is extended with color dilution genes such as cream, dun, silver dapple and champagne and also with white pattern genes at white, grey, roan, tobiano, overo and leopard spotting loci. Till date no sex-linked coat color inheritance has been reported in horses unlike in mice, Syrian hamster and cat.
Recent developments in molecular tools have given access to DNA information and provide genotypes of the animals. The most significant application so far has been for parentage testing.
The molecular genetic basis of disease associated with the coat color viz., overo white foal syndrome has been identified and genetic counselling has been provided by different dedicated laboratories to reduce the incidence or possible occurrence of this dominant trait.
Allele specific tests allow owners to choose a horses sire and dam combinations that avoid production of genetically defective offspring.
Some of the colors of the foal at the time of birth is confusing because of the presence of different color patterns and only with minor variations; however with the recent molecular genetic techniques the color patterns such as chestnut, black, cream, overo, sabino, tobiano, white, roan and silver dapple could be identified accurately.
However, further studies are needed to identify the genes responsible for other color patterns viz., grey, dun, champagne, appaloosa/leopard complex and dominant black colors, variable color patterns due to shade, scooty and mealy effects, white markings in the face and leg and mane and tail color variations of the chestnut, sorrel and palomino horses.
The generation of complete genome sequence of horses will contribute to unravelling the genetic basis of phenotypic variation namely mutation and biochemical pathways associated with normal and mutated genes that affect coat color and associated traits. This will be applied in breeding programs to reduce the incidence of disease and to increase the production efficiency.
In future it is assumed that the rapidly expanding genomic data will facilitate the identification of genes involved in complex traits.
The following online reference will provide you with an easy understand information about breeding miniature horses, for which color is a component to their economic value.
http://miniaturehorses-cruzmountain.com
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