Biology of epidermal and hair pigmentation in cattle: a mini‐review

Abstract

Coat colours in cattle have been of interest to both breeders and researchers as genes regulating pigmentation not only affect the phenotype but also have economic implications in the event of genetic mutations. The genes controlling pigmentation act as a complex and interact with each other to cause phenotypic and genotypic variations. Pigmentation of coat broadly depends on the ratio of eumelanin and pheomelanin, the two components of melanin. Increase in eumelanin imparts a black coat colour while raise in pheomelanin is responsible for a yellowish or reddish colour. The main enzymes responsible for melanogenesis are regulated by the genes of the tyrosinase family. It is speculated that the wild-type gene present in the ancestral breeds of the present day cattle have more pheomelanin content and that, over time, mutations have introduced more variations leading to many shades. This could have occurred either because of interactions or because of deletions in the responsible genes. The environmental conditions have also contributed to mutations in these genes, helping in the adaptability of the animals to different geographical regions. The switching between the syntheses of melanin components depends on several genes like melanocortin-1receptor gene (MC1r) - also known as melanocyte-stimulating hormone receptor gene (MSHr)-, agouti (A), attractin (Atrn) and mahogunin (Mgrn1). The purpose of this review is to summarize the recent advances in the field of pigment biology and to highlight possible areas of research that may benefit a breeder or a farmer in the selection of animals on the basis of phenotype.

Whole-Genome Analyses of Korean Native and Holstein Cattle Breeds by Massively Parallel Sequencing

“…The SNP detected in Holstein should be corresponded with E D locus as well. The brindle pattern in Chikso requires at least one wild-type MC1R in the absence of a dominant allele [44], [45], and is consistent with a lack of SNPs in MC1R in the Chikso sequence. Because coat color involves multiple genes and remains incompletely understood in cattle, the information provided here should be a useful resource for clarifying its underlying genetic mechanisms in cattle.…”

“…For example, several nsSNPs occurred in pigmentation-related genes, such as tyrosinase, tyrosinase-related protein 1, dopachrome tautomerase, and melanocortin 1 receptor ( MC1R ) (Table S11). Coat color and pattern in cattle is a main breed characteristic, and it depends on the relative presence of phenomelanin and eumelanin produced by melanocytes [44]. Each of the four breeds in this study has a unique coat color: brown in Hanwoo, black in Jeju Heugu, brindle (tiger-striped) in Chikso, and black and white in Korean Holstein (Fig.…”

Admixture mapping of tuberculosis and pigmentation-related traits in an African–European hybrid cattle population

“…This gene is known to regulate the level of tyrosinase enzyme production which is responsible for the switch between phaeomelanin (red pigment) and eumelanin (black pigment) production. The dominant MC1R gene has been described as associating with black coat color and a recessive allele results in red coat color (Seo et al, 2007). The Z -score was a positive value indicating that the ancestral signal originates within East African zebu.…”

Antitumor properties of aloe-emodin and induction of transglutaminase 2 activity in B16–F10 melanoma cells

“…1.14.18.1) and dopachrome tautomerase (DCT, E.C. 5.3.2.3) play a key role (Seo et al 2007). Malignant melanoma originates from melanocytes in the basal layer of the epidermis and its incidence is rapidly increasing.…”