Dominant Red

The MC1R gene is a major determinant of black and red coat color in Holstein-Friesian cattle. This gene encodes a protein responsible for the type of pigment that exists in the pigment cells of the skin. Coat color in Holstein cattle corresponds to alleles: the dominant one encodes black color, the recessive one encodes red color. This combination shows that the vast majority of Holstein cattle are characterized by black and white coat. In addition to the two most common alleles in the genotype, there are two rarer ones: one that determines the wild color and the black-red color, which changes with the life of the growing individual.

The MC1R gene is not the only gene responsible for cattle coat color. An independent gene ultimately determining the color of cattle is the COPA – Dominant Red gene, located on chromosome 3 (BTA3). It is involved in the synthesis of pigmentation and is completely associated with the dominance of red color in cattle. This mutation shows no negative effects within animal welfare.

Taking into account the above conclusions, individuals possessing a pair of recessive alleles of the MC1R gene will be characterized by red coat color. In such a situation, the COPA gene does not affect the color. On the other hand, if an individual shows at least one dominant allele of black color then the final color of the coat depends on the COPA gene. Cattle showing the Dominant Red variant in their genotype will have a red coat color. Otherwise, the individual has a coat color dependent only on the MC1R gene.

REFERENCES #

1. Dorshorst B, Henegar C, Liao X, Sällman Almén M, Rubin CJ, Ito S, Wakamatsu K, Stothard P, Van Doormaal B, Plastow G, Barsh GS & Andersson L. Dominant Red Coat Color in Holstein Cattle Is Associated with a Missense Mutation in the Coatomer Protein Complex, Subunit Alpha (COPA) Gene. (2015). PLoS One 4;10(6).