New Test for Chestnut Coat Color Genes in Horses Available

Chestnut is not considered an acceptable coat color in some breeds of horses. A fast, cost-effective, and reliable method for the routine genotyping of alleles has been developed by Researchers from the Department of Genetics, Physical Anthropology and Animal Physiology at the University of the Basque Country in Bilbao, Spain.

Chestnut coat color is due to two recessive versions (e and ea) of the gene called melanocortin-1 receptor. The dominant version of the gene (E) produces black or bay coats.

For the pony breeds of the Cantabrian Coast of the Iberian Peninsula, bay and black are considered to be the original coat colors. Researchers believe that around 1930 local mares were crossed with stallions of other breeds to "improve the capacity for agricultural work and meat production." This also resulted in some chestnut offspring, which are not allowed in the official stud book in the Cantabrian Coast pony breeds.

SNaPshot is a tool capable of detecting single variations in DNA called single nucleotide polymorphisms (SNPs) such as the E, e, and ea versions of the gene responsible for the chestnut coat color in horses.

This study of 249 horses from northern Spain revealed that SNaPshot is robust, reliable, reproducible, fast, simple, and cost-effective.

The authors also stated, "this methodology, proven in this study to be useful for four Cantabrian Coast horse breeds, it is not exclusive to these horse breeds; rather, could be extended to any horse breed and, therefore, to any breeders association, which needs to know the 'chestnut coat color' associated phenotype for a certain reproductive animal."

The full-length article, "Identification of horse chestnut coat color genotype using SNaPshot(R)," was published in the December 2009 edition of the journal BMC Research Notes.

About the Author

Stacey Oke, DVM, MSc

Stacey Oke, MSc, DVM, is a practicing veterinarian and freelance medical writer and editor. She is interested in both large and small animals, as well as complementary and alternative medicine. Since 2005, she's worked as a research consultant for nutritional supplement companies, assisted physicians and veterinarians in publishing research articles and textbooks, and written for a number of educational magazines and websites.

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