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Home / Equine Research Bank / Sci Rep / An epistatic effect of KRT25 on SP6 is involved in curly coa...
Scientific reports2018; 8(1); 6374; doi: 10.1038/s41598-018-24865-3

An epistatic effect of KRT25 on SP6 is involved in curly coat in horses.

Abstract: Curly coat represents an extraordinary type of coat in horses, particularly seen in American Bashkir Curly Horses and Missouri Foxtrotters. In some horses with curly coat, a hypotrichosis of variable extent was observed, making the phenotype appear more complex. In our study, we aimed at investigating the genetic background of curly coat with and without hypotrichosis using high density bead chip genotype and next generation sequencing data. Genome-wide association analysis detected significant signals (p = 1.412 × 10-05-1.102 × 10-08) on horse chromosome 11 at 22-35 Mb. In this significantly associated region, six missense variants were filtered out from whole-genome sequencing data of three curly coated horses of which two variants within KRT25 and SP6 could explain all hair phenotypes. Horses heterozygous or homozygous only for KRT25 variant showed curly coat and hypotrichosis, whereas horses with SP6 variant only, exhibited curly coat without hypotrichosis. Horses with mutant alleles in both variants developed curly hair and hypotrichosis. Thus, mutant KRT25 allele is masking SP6 allele effect, indicative for epistasis of KRT25 variant over SP6 variant. In summary, genetic variants in two different genes, KRT25 and SP6, are responsible for curly hair. All horses with KRT25 variant are additionally hypotrichotic due to the KRT25 epistatic effect on SP6.
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Publication Date: 2018-04-23 PubMed ID: 29686323PubMed Central: PMC5913262DOI: 10.1038/s41598-018-24865-3Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The study provides deep insights into the genetic factors causing the curly coat appearance in horses, particularly found in American Bashkir Curly Horses and Missouri Foxtrotters. Through the use of genome-wide sequencing, the researchers identify variants in two specific genes, KRT25 and SP6, that contribute to this phenotype.

Background

  • The research investigates the genetic background of the curly coat phenotype in horses, a peculiar coat texture observed predominantly in American Bashkir Curly Horses and Missouri Foxtrotters. Some of these horses also show hypotrichosis, a condition characterized by lesser hair than usual, adding complexity to the phenotype.

Methods

  • Researchers used high density bead chip genotype and next generation sequencing data to explore the genetic cause of this distinctive coat texture.
  • A genome-wide association analysis was conducted, which produced significant signals in a certain region on horse chromosome 11.

Findings

  • From the significantly associated region, six missense variants were sifted out from the genome sequencing data of three curly coated horses. Out of these six, two variants within KRT25 and SP6 were found to explain all hair phenotypes.
  • Horses only carrying the KRT25 variant showed both curly coat and hypotrichosis, while those only carrying the SP6 variant demonstrated curly coat but without hypotrichosis.
  • Horses carrying mutant alleles in both genes manifested both curly hair and hypotrichosis. This suggests that the mutant KRT25 allele masks the effect of the SP6 allele, indicative of an epistasis of the KRT25 variant over the SP6 variant.

Conclusion

  • The findings suggest that genetic variants in both KRT25 and SP6 genes are responsible for the formation of curly hair in horses.
  • Horses carrying the KRT25 variant also exhibit hypotrichosis due to a dominant effect of the KRT25 gene over SP6, referred to as the KRT25 epistatic effect on SP6.

Cite This Article

APA
Thomer A, Gottschalk M, Christmann A, Naccache F, Jung K, Hewicker-Trautwein M, Distl O, Metzger J. (2018). An epistatic effect of KRT25 on SP6 is involved in curly coat in horses. Sci Rep, 8(1), 6374. https://doi.org/10.1038/s41598-018-24865-3

Publication

Scientific reports
ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 8
Issue: 1
Pages: 6374

Researcher Affiliations

Thomer, Annika
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany.
Gottschalk, Maren
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany.
Christmann, Anna
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany.
Naccache, Fanny
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany.
Jung, Klaus
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany.
Hewicker-Trautwein, Marion
  • Department of Pathology, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany.
Distl, Ottmar
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany. ottmar.distl@tiho-hannover.de.
Metzger, Julia
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover Foundation, Hannover, 30559, Germany.

MeSH Terms

  • Animal Fur / chemistry
  • Animals
  • Chromosomes, Mammalian
  • Epistasis, Genetic
  • Genome-Wide Association Study
  • Genotype
  • High-Throughput Nucleotide Sequencing
  • Horses / genetics
  • Horses / physiology
  • Hypotrichosis / genetics
  • Keratins, Hair-Specific / genetics
  • Phenotype
  • Polymorphism, Single Nucleotide
  • Sp Transcription Factors / genetics

Conflict of Interest Statement

The authors declare no competing interests.

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