A deletion in the MC1R gene alters coat color in Guzerat cattle.

Hair coat is one of the traits most widely used for breed qualification and its phenotypic variations are essential for the identification of cattle breeds.1 Coat color is also associated with adaptive traits of thermoregulation.2 The protein synthesized by the MC1R gene plays an important role in the regulation of the type of melanin produced.3 Polymorphisms in these genes are associated with variations in coat color and the trait is almost exclusively determined genetically.4 Indicine Guzerat cattle are a dual‐purpose breed (meat and milk)5 and a gray coat is one of their breed qualifications. However, the birth of a single red individual was reported as a result of the mating of two gray Guzerat animals. Therefore, the aim of the present study was to identify variations in the MC1R gene that would be associated with the variation in coat color of this animal.

Eleven Guzerat animals were used in the study. Ten cows had a gray coat and one cow, called 'Cenoura' ('Carrot', in a free translation), had a red coat (Fig. 1a). The red cow was born to a sire and a cow of the same breed with gray coat color. DNA was extracted from hair follicles. The primer pair described by Goud et␣al.6 was used for PCR, which amplifies the single exon of the MC1R gene. Sequence analysis permitted the detection of a deletion of one nucleotide whose nitrogenated base is a thymine, at position 311 of the MC1R gene. This deletion causes a change in the reading frame from this point onwards (amino acid 104) and creates a premature stop codon. The predicted protein is smaller, with 155 amino acids compared with the original protein (317 amino acids; Fig. 1b). In addition to the deletion, two SNPs were detected in the gene of the red animal. The first SNP is located at position 583 (C>T) and the other at position 663 (T>C). The two polymorphisms found are located after the predicted stop codon and do not interfere with the amino acid composition of the new protein. The generated sequences were deposited at NCBI under accession nos MZ361079 and MZ361080.

Polymorphisms in the MC1R gene are frequently associated with changes in the coat color of domestic animals, including cattle.6,7 We therefore believe that this deletion is the mutation responsible for the red coat of the Guzerat cow studied. The frequency of occurrence of this coat color is very low. The biological knowledge provided by the report highlights the importance of the gene for coat color and should encourage future studies investigating similar variations using this gene as a candidate gene.

We thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico for the fellowship granted to the first author. We also thank Mr Davi Teixeira for allowing the collection of biological material on his farm (Marca Vi ‐ Fazenda Água Doce, Itagibá‐BA, Brazil).

The authors declare no potential conflicts of interest.

Data are available at GenBank, accession nos MZ361079 and MZ361080.