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Home / Equine Research Bank / PLoS One / Identification of genomic loci associated with Rhodococcus e...
PloS one2014; 9(6); e98710; doi: 10.1371/journal.pone.0098710

Identification of genomic loci associated with Rhodococcus equi susceptibility in foals.

Abstract: Pneumonia caused by Rhodococcus equi is a common cause of disease and death in foals. Although agent and environmental factors contribute to the incidence of this disease, the genetic factors influencing the clinical outcomes of R. equi pneumonia are ill-defined. Here, we performed independent single nucleotide polymorphism (SNP)- and copy number variant (CNV)-based genome-wide association studies to identify genomic loci associated with R. equi pneumonia in foals. Foals at a large Quarter Horse breeding farm were categorized into 3 groups: 1) foals with R. equi pneumonia (clinical group [N = 43]); 2) foals with ultrasonographic evidence of pulmonary lesions that never developed clinical signs of pneumonia (subclinical group [N = 156]); and, 3) foals without clinical signs or ultrasonographic evidence of pneumonia (unaffected group [N = 49]). From each group, 24 foals were randomly selected and used for independent SNP- and CNV-based genome-wide association studies (GWAS). The SNP-based GWAS identified a region on chromosome 26 that had moderate evidence of association with R. equi pneumonia when comparing clinical and subclinical foals. A joint analysis including all study foals revealed a 3- to 4-fold increase in odds of disease for a homozygous SNP within the associated region when comparing the clinical group with either of the other 2 groups of foals or their combination. The region contains the transient receptor potential cation channel, subfamily M, member 2 (TRPM2) gene, which is involved in neutrophil function. No associations were identified in the CNV-based GWAS. Collectively, these data identify a region on chromosome 26 associated with R. equi pneumonia in foals, providing evidence that genetic factors may indeed contribute to this important disease of foals.
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Publication Date: 2014-06-03 PubMed ID: 24892408PubMed Central: PMC4043894DOI: 10.1371/journal.pone.0098710Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • Non-P.H.S.

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 is about the genetic factors that may influence susceptibility to Rhodococcus equi pneumonia in foals. The study identified a region on chromosome 26 that is linked to the disease, with particular focus on a gene involved in neutrophil function.

Section 1: Background and Objective of the Research

  • The study focuses on identifying genetic factors that influence susceptibility to Rhodococcus equi pneumonia in foals. Rhodococcus equi is a bacterium that causes pneumonia, a common disease, and cause of death among foals.
  • The objective is to identify genomic loci associated with this disease. Although it is known that both agent and environmental factors contribute to the disease, the genetic factors remain unclear.

Section 2: Methodology

  • The researchers carried out independent genome-wide association studies (GWAS) based on single nucleotide polymorphism (SNP) and copy number variant (CNV).
  • The study was conducted on a large Quarter Horse breeding farm, and foals were put into three categories: foals with R. equi pneumonia (clinical group), foals with evidence of pulmonary disease but no clinical signs of pneumonia (subclinical group), and foals with no signs or evidence of pneumonia (unaffected group).
  • Randomly selected samples from each group were used for the GWAS.

Section 3: Findings

  • The SNP-based GWAS found moderate evidence of a region on chromosome 26 associated with R. equi pneumonia by comparing clinical and subclinical foals. This region houses the TRPM2 gene, which is related to neutrophil function. Neutrophils are white blood cells pivotal in the body’s defense against bacterial infections.
  • When all studies were analyzed together, there was a 3-4 times increase in risk for carrying a homozygous SNP within this region when comparing the clinical group with either the subclinical, unaffected groups, or their combination.
  • By contrast, the CNV-based GWAS did not identify any associations.

Section 4: Conclusion

  • The findings demonstrate a region on chromosome 26 associated with R. equi pneumonia in foals, providing evidence that genetic factors may contribute to this significant disease of foals.

Cite This Article

APA
McQueen CM, Doan R, Dindot SV, Bourquin JR, Zlatev ZZ, Chaffin MK, Blodgett GP, Ivanov I, Cohen ND. (2014). Identification of genomic loci associated with Rhodococcus equi susceptibility in foals. PLoS One, 9(6), e98710. https://doi.org/10.1371/journal.pone.0098710

Publication

PloS one
ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 9
Issue: 6
Pages: e98710

Researcher Affiliations

McQueen, Cole M
  • Department of Large Animal Clinical Sciences, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America.
Doan, Ryan
  • Department of Veterinary Pathobiology, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America.
Dindot, Scott V
  • Department of Veterinary Pathobiology, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America; Department of Molecular and Cellular Medicine, Texas A&M University College of Medicine, College Station, Texas, United States of America.
Bourquin, Jessica R
  • Department of Large Animal Clinical Sciences, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America.
Zlatev, Zlatomir Z
  • Department of Electrical and Computer Engineering, Texas A&M University Dwight Look College of Engineering, College Station, Texas, United States of America.
Chaffin, M Keith
  • Department of Large Animal Clinical Sciences, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America.
Blodgett, Glenn P
  • 6666 Ranch, 1102 Dash For Cash Road, Guthrie, Texas, United States of America.
Ivanov, Ivan
  • Department of Veterinary Physiology & Pharmacology, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America.
Cohen, Noah D
  • Department of Large Animal Clinical Sciences, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, Texas, United States of America.

MeSH Terms

  • Animals
  • Disease Susceptibility
  • Genome-Wide Association Study / methods
  • Horse Diseases / genetics
  • Horse Diseases / microbiology
  • Horses
  • Pneumonia, Bacterial / genetics
  • Polymorphism, Single Nucleotide / genetics
  • Rhodococcus equi / pathogenicity

Conflict of Interest Statement

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

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Citations

This article has been cited 6 times.
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