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HLA2023; 102(4); 489-500; doi: 10.1111/tan.15078

Newly identified variability of the antigen binding site coding sequences of the equine major histocompatibility complex class I and class II genes.

Abstract: The major histocompatibility complex (MHC) with its class I and II genes plays a crucial role in the immune response to pathogens by presenting oligopeptide antigens to various immune response effector cells. In order to counteract the vast variability of infectious agents, MHC class I and II genes usually retain high levels of SNPs mainly concentrated in the exons encoding the antigen binding sites. The aim of the study was to reveal new variability of selected MHC genes with a special focus on MHC class I physical haplotypes. Long-range NGS to was used to identify exon 2-exon 3 alleles in three genetically distinct horse breeds. A total of 116 allelic variants were found in the MHC class I genes Eqca-1, Eqca-2, Eqca-7 and Eqca-Ψ, 112 of which were novel. The MHC class II DRA locus was confirmed to comprise five exon 2 alleles, and no new sequences were observed. Additional variability in terms of 15 novel exon 2 alleles was identified in the DQA1 locus. Extensive overall variability across the entire MHC region was confirmed by an analysis of MHC-linked microsatellite loci. Both diversifying and purifying selection were detected within the MHC class I and II loci analyzed.
© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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Publication Date: 2023-04-27 PubMed ID: 37106476DOI: 10.1111/tan.15078Google 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 examined the variation in antigen binding site coding sequences of major histocompatibility complex (MHC) genes in horses. Ligand-NGS was used to discover 116 allelic variants, including 112 newly identified alleles. The study confirmed significant variability across the MHC region and both diversifying and purifying selectivity within MHC class I and II loci.

Background on Major Histocompatibility Complex (MHC)

  • The Major Histocompatibility Complex (MHC) and its class I and II genes have key roles in the immune response to pathogens. They function as presenters of oligopeptide antigens to various cells involved in the immune response.
  • In response to the vast variability of infectious agents, MHC class I and II genes typically maintain high levels of Single Nucleotide Polymorphisms (SNPs), primarily focused in the exons encoding the antigen binding sites.

Research Goals and Methods

  • The primary aim of this study was to uncover new variability in selected MHC genes, with a particular focus on MHC class I physical haplotypes.
  • The method used was long-range Next-Generation Sequencing (NGS) to discover exon 2-exon 3 alleles in three genetically distinct horse breeds.

Key Findings

  • A total of 116 allelic variants were identified in MHC class I genes Eqca-1, Eqca-2, Eqca-7 and Eqca-ψ in the horse breeds studied. Out of these, 112 were new findings.
  • The research confirmed the MHC class II DRA locus comprises five exon 2 alleles, with no new sequences observed.
  • Additional variability was detected in the form of 15 new exon 2 alleles in the DQA1 locus.
  • By analyzing MHC-linked microsatellite loci, the researchers confirmed extensive overall variability across the entire MHC region.

Selection within MHC Class I and II loci

  • Both diversifying and purifying selection were observed within the MHC class I and II loci studied, showing that there are evolutionary forces acting to both increase and maintain variation.

Cite This Article

APA
Plasil M, Oppelt J, Klumplerova M, Bubenikova J, Vychodilova L, Janova E, Stejskalova K, Futas J, Knoll A, Leblond A, Mihalca AD, Horin P. (2023). Newly identified variability of the antigen binding site coding sequences of the equine major histocompatibility complex class I and class II genes. HLA, 102(4), 489-500. https://doi.org/10.1111/tan.15078

Publication

HLA
ISSN: 2059-2310
NlmUniqueID: 101675570
Country: England
Language: English
Volume: 102
Issue: 4
Pages: 489-500

Researcher Affiliations

Plasil, Martin
  • Research group Animal Immunogenomics, CEITEC VETUNI, University of Veterinary Sciences Brno, Brno, Czechia.
Oppelt, Jan
  • Research group Animal Immunogenomics, CEITEC VETUNI, University of Veterinary Sciences Brno, Brno, Czechia.
Klumplerova, Marie
  • Research group Animal Immunogenomics, CEITEC VETUNI, University of Veterinary Sciences Brno, Brno, Czechia.
Bubenikova, Jana
  • Research group Animal Immunogenomics, CEITEC VETUNI, University of Veterinary Sciences Brno, Brno, Czechia.
Vychodilova, Leona
  • Department of Animal Genetics, Faculty of Veterinary Medicine, University of Veterinary Sciences Brno, Brno, Czechia.
Janova, Eva
  • Research group Animal Immunogenomics, CEITEC VETUNI, University of Veterinary Sciences Brno, Brno, Czechia.
Stejskalova, Karla
  • Department of Animal Genetics, Faculty of Veterinary Medicine, University of Veterinary Sciences Brno, Brno, Czechia.
Futas, Jan
  • Research group Animal Immunogenomics, CEITEC VETUNI, University of Veterinary Sciences Brno, Brno, Czechia.
Knoll, Ales
  • Department of Animal Morphology, Physiology and Genetics, Faculty of Agronomy, Mendel University in Brno, Brno, Czechia.
Leblond, Agnes
  • Clinical Department of Companion, Leisure & Sport Animals, INRAE-VetAgro Sup, Campus vétérinaire de Lyon, Marcy L'Etoile, France.
Mihalca, Andrei D
  • Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Cluj-Napoca, Romania.
Horin, Petr
  • Research group Animal Immunogenomics, CEITEC VETUNI, University of Veterinary Sciences Brno, Brno, Czechia.

MeSH Terms

  • Horses / genetics
  • Animals
  • Genes, MHC Class II
  • Alleles
  • Histocompatibility Antigens Class I
  • Exons / genetics
  • Histocompatibility Antigens Class II / genetics
  • Major Histocompatibility Complex
  • Binding Sites

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Citations

This article has been cited 4 times.
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