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Animal genetics2022; 53(5); 549-556; doi: 10.1111/age.13240

Roan coat color in livestock.

Abstract: Since domestication, a wide variety of phenotypes including coat color variation has developed in livestock. This variation is mostly based on selective breeding. During the beginning of selective breeding, potential negative consequences did not become immediately evident due to low frequencies of homozygous animals and have been occasionally neglected. However, numerous studies of coat color genetics have been carried out over more than a century and, meanwhile, pleiotropic effects for several coat color genes, including disorders of even lethal impact, were described. Similar coat color phenotypes can often be found across species, caused either by conserved genes or by different genes. Even in the same species, more than one gene could cause the same or similar coat color phenotype. The roan coat color in livestock species is characterized by a mixture of white and colored hair in cattle, pig, sheep, goat, alpaca, and horse. So far, the genetic background of this phenotype is not fully understood, but KIT and its ligand KITLG (MGF) are major candidate genes in livestock species. For some of these species, pleiotropic effects such as subfertility in homozygous roan cattle or homozygous embryonic lethality in certain horse breeds have been described. This review aims to point out the similarities and differences of the roan phenotype across the following livestock species: cattle, pig, sheep, goat, alpaca, and horse; and provides the current state of knowledge on genetic background and pleiotropic effects.
Publication Date: 2022-07-10 PubMed ID: 35811453DOI: 10.1111/age.13240Google Scholar: Lookup
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  • Journal Article
  • Review

Summary

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This research article reviews and provides insights into the genetics behind roan coat color in various livestock species, including cattle, pig, sheep, goat, alpaca, and horse. It also discusses the potential adverse effects associated with such genetic traits.

Overview of Coat Color Variation in Livestock

  • The research explains that livestock’s varied coat colors are primarily a result of selective breeding. This diversity has evolved over time since the domestication of these animals.
  • The researchers acknowledge that the possible negative impacts of selective breeding weren’t initially accounted for due to the low frequencies of homozygous animals. These consequences were often overlooked or neglected.

Pleiotropic Effects and the Genetics of Coat Color

  • Over the last century, numerous studies have investigated coat color genetics, discovering “pleiotropic effects.” These are impacts where a single gene influences multiple seemingly unrelated physical traits.
  • The authors note that for genes influencing coat color, these effects might include disorders or lethal impacts.
  • Interestingly, similar coat color phenotypes often occur across species, either induced by conserved genes or different ones. This implies that more than one gene can trigger the same or similar coat color phenotype within the same species.

The Roan Phenotype in Livestock Species

  • The paper focuses on the roan coat color, a pattern characterized by a mixture of white and colored hair, found in several livestock species.
  • The genetic background of this phenotype remains largely undiscovered, but the KIT and KITLG genes are identified as major candidate genes influencing this trait in livestock.
  • Pleiotropic impacts associated with roan coat color are also discussed, such as subfertility in homozygous roan cattle or embryonic lethality in certain horse breeds.

Objective of the Review

  • This review is aimed to highlight the similarities and differences of the roan phenotype across livestock species including cattle, pigs, sheep, goats, alpacas, and horses.
  • The paper presents the latest understanding on the genetic background and pleiotropic effects linked to the roan coat color across these species.

Cite This Article

APA
Voß K, Blaj I, Tetens JL, Thaller G, Becker D. (2022). Roan coat color in livestock. Anim Genet, 53(5), 549-556. https://doi.org/10.1111/age.13240

Publication

ISSN: 1365-2052
NlmUniqueID: 8605704
Country: England
Language: English
Volume: 53
Issue: 5
Pages: 549-556

Researcher Affiliations

Voß, Katharina
  • Institute of Animal Breeding and Husbandry, University of Kiel, Kiel, Germany.
Blaj, Iulia
  • Institute of Animal Breeding and Husbandry, University of Kiel, Kiel, Germany.
Tetens, Julia L
  • Institute of Animal Breeding and Husbandry, University of Kiel, Kiel, Germany.
Thaller, Georg
  • Institute of Animal Breeding and Husbandry, University of Kiel, Kiel, Germany.
Becker, Doreen
  • Institute of Genome Biology, Research Institute for Farm Animal Biology (FBN), Dummerstorf, Germany.

MeSH Terms

  • Animals
  • Camelids, New World
  • Cattle / genetics
  • Color
  • Goats / genetics
  • Hair Color / genetics
  • Horses / genetics
  • Livestock / genetics
  • Phenotype
  • Sheep
  • Stem Cell Factor / genetics
  • Swine

Grant Funding

  • H. Wilhelm Schaumann Stiftung

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