Red factor is a genetic trait related to red coat colour in cattle. The main gene that regulates the switch between synthesis of black (eumelanin) or red-brown pigment (pheomelanin) is MC1R (melanocyte-stimulating hormone receptor). Red factor is inherited as an autosomal recessive trait therefore only homozygous animals (ee) express red coat colour.

In our laboratory we currently offer the red factor test that detects 4 different mutations in MC1R gene. The test detects alleles E^D, E⁺, e, e^v1 and e^v2. E^D allele is dominant over other alleles. All animals with E^D are black. When there are no mutations on alleles E^D, e, e^v1 and e^v2 animal’s genotype is E⁺ and can be black or red. Animals with red coat colour are homozygous for alleles e, e^v1 and e^v2. The test does not detect further possible mutations, which can also cause red coat colour in some animals.

Mutation: MC1R gene

DNA test sample: EDTA whole blood (1.0 ml), buccal swabs, hair, semen.