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Home / Equine Research Bank / PLoS One / A genome-wide association study identifies risk loci to equi...
PloS one2013; 8(8); e71619; doi: 10.1371/journal.pone.0071619

A genome-wide association study identifies risk loci to equine recurrent uveitis in German warmblood horses.

Abstract: Equine recurrent uveitis (ERU) is a common eye disease affecting up to 3-15% of the horse population. A genome-wide association study (GWAS) using the Illumina equine SNP50 bead chip was performed to identify loci conferring risk to ERU. The sample included a total of 144 German warmblood horses. A GWAS showed a significant single nucleotide polymorphism (SNP) on horse chromosome (ECA) 20 at 49.3 Mb, with IL-17A and IL-17F being the closest genes. This locus explained a fraction of 23% of the phenotypic variance for ERU. A GWAS taking into account the severity of ERU, revealed a SNP on ECA18 nearby to the crystalline gene cluster CRYGA-CRYGF. For both genomic regions on ECA18 and 20, significantly associated haplotypes containing the genome-wide significant SNPs could be demonstrated. In conclusion, our results are indicative for a genetic component regulating the possible critical role of IL-17A and IL-17F in the pathogenesis of ERU. The associated SNP on ECA18 may be indicative for cataract formation in the course of ERU.
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Publication Date: 2013-08-14 PubMed ID: 23977091PubMed Central: PMC3743750DOI: 10.1371/journal.pone.0071619Google 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 research conducted a genome-wide association study on German warmblood horses to identify genetic risk factors linked to equine recurrent uveitis, a common eye disease in horses, and found significant single nucleotide polymorphisms on horse chromosomes that may influence the disease’s occurrence and severity.

Objective and Methodology

  • The research article focused on investigating risk loci or places in the genetic code linked to Equine Recurrent Uveitis (ERU), an eye condition prevalent among 3-15% of the horse population. The disease is recurrent, meaning it happens repeatedly over time.
  • The researchers conducted a Genome-Wide Association Study (GWAS), a common method used to identify genes associated with particular diseases. The study uses the Illumina equine SNP50 bead chip.
  • The study collected and analyzed a sample that consists of 144 German warmblood horses, a particular breed of horses. This research method is targeted and specific, intending to establish robust and reliable findings.

Study Findings

  • The GWAS found a significant connection between ERU and a specific single nucleotide polymorphism (SNP) on horse chromosome 20 (ECA 20) at 49.3 Mb. SNPs are variations at a single position in a DNA sequence among individuals. They can naturally occur in the DNA sequence and are frequently used in defining biological markers for diseases.
  • Two closest genes to the identified SNP on ECA 20 are IL-17A and IL-17F. These genes are potentially important in the pathogenesis or the development of ERU. They contribute to an estimated 23% of the phenotypic variance for ERU. Phenotypic variance refers to the observable physical or biochemical differences in an individual attributed to individual genetic traits.
  • A secondary GWAS that considered the severity of ERU found another significant SNP on ECA18, close to the crystalline gene cluster CRYGA-CRYGF. This region might have implications on cataract formation during the progression of ERU.
  • Further, the research also demonstrated considerable associated haplotypes within the genome-wide significant SNPs on ECA18 and 20. Haplotypes are a set of DNA variations, or polymorphisms, that tend to be inherited together and can be used to track the inheritance of disease in families.

Conclusion and Implications

  • Findings from the research suggest a genetic component in the regulation of the critical role of IL-17A and IL-17F in the development of ERU. Understanding these genetic components can lead to better prediction, prevention, and treatment strategies for this recurrent eye disease in horses.
  • The identified SNP on ECA18 may play a pivotal role in cataract formation in the process of ERU, providing another potential research direction for efforts to mitigate the effects of ERU in the horse population.

Cite This Article

APA
Kulbrock M, Lehner S, Metzger J, Ohnesorge B, Distl O. (2013). A genome-wide association study identifies risk loci to equine recurrent uveitis in German warmblood horses. PLoS One, 8(8), e71619. https://doi.org/10.1371/journal.pone.0071619

Publication

PloS one
ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 8
Issue: 8
Pages: e71619

Researcher Affiliations

Kulbrock, Maike
  • Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Hannover, Germany ; Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.
Lehner, Stefanie
    Metzger, Julia
      Ohnesorge, Bernhard
        Distl, Ottmar

          MeSH Terms

          • Animals
          • Case-Control Studies
          • Genetic Loci / genetics
          • Genetic Predisposition to Disease
          • Genome-Wide Association Study
          • Germany
          • Horse Diseases / genetics
          • Horses / genetics
          • Linear Models
          • Recurrence
          • Risk Factors
          • Uveitis / genetics
          • Uveitis / veterinary

          Conflict of Interest Statement

          Competing Interests: The authors have declared that no competing interests exist.

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          This article has been cited 18 times.
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