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Genes2020; 11(12); doi: 10.3390/genes11121518

Distribution of the Warmblood Fragile Foal Syndrome Type 1 Mutation (PLOD1 c.2032G>A) in Different Horse Breeds from Europe and the United States.

Abstract: Warmblood fragile foal syndrome (WFFS) is an autosomal recessive disorder caused by a single nucleotide variant in the procollagen-lysine-2-oxoglutarate-5-dioxygenase 1 gene (PLOD1:c.2032G>A, p.Gly678Arg). Homozygosity for the PLOD1 variant causes an Ehler-Danlos-like syndrome, which has to date only been reported in warmblood breeds but the WFFS allele has been also detected in the Thoroughbred. To investigate the breed distribution of the WFFS allele, 4081 horses belonging to 38 different breeds were screened. In total, 4.9% of the horses representing 21 breeds carried the WFFS allele. The affected breeds were mainly warmbloods, with carrier frequency as high as 17% in the Hanoverian and Danish Warmblood. The WFFS allele was not detected in most non-warmblood breeds. Exceptions include WFFS carriers in the Thoroughbred (17/716), Haflinger (2/48), American Sport Pony (1/12), and Knabstrupper (3/46). The origin of the WFFS allele remains unknown. The Arabian breed and specifically the stallion Bairactar Or. Ar. (1813), whose offspring were reported to have a similar phenotype in the 19th century, were hypothesized as the origin. DNA from a museum sample of Bairactar Or. Ar. showed that he did not carry the mutated allele. This result, together with the genotypes of 302 Arabians, all homozygous for the reference allele, does not support an Arabian origin of the WFFS allele. Our extensive survey shows the WFFS allele to be of moderate frequency and concern in warmbloods and also in breeds where it may not be expected.
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Publication Date: 2020-12-18 PubMed ID: 33353040PubMed Central: PMC7766603DOI: 10.3390/genes11121518Google Scholar: Lookup
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  • Journal Article
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  • Non-U.S. Gov't

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 examines the occurrence of the Warmblood Fragile Foal Syndrome (WFFS) mutation among diverse horse breeds in Europe and the United States. Results identify a significant prevalence of the mutation, particularly in warmblood breeds, challenging assumptions about its origin and distribution.

Objective and Methodology

  • The purpose of this research was to evaluate the distribution of the Warmblood Fragile Foal Syndrome (WFFS) gene variant (PLOD1:c.2032G>A, p.Gly678Arg) among different horse breeds in Europe and the United States.
  • The research involved the genomic screening of 4081 horses, encompassing 38 different breeds.
  • The researchers had hypothesized that the source of the WFFS allele was the Arabian breed, specifically the stallion Bairactar Or. Ar. To test this hypothesis, the DNA from a museum sample of Bairactar Or. Ar was analyzed in addition to the genotypes of 302 Arabians.

Key Findings

  • The research discovered that 4.9% of the horses, representing 21 breeds, carried the WFFS allele.
  • The breeds impacted were predominantly warmbloods with carrier frequency reaching up to 17% in breeds such as the Hanoverian and Danish Warmblood.
  • Although the WFFS allele was mostly absent in non-warmblood breeds, there were some carriers found in the Thoroughbred (17/716), Haflinger (2/48), American Sport Pony (1/12), and Knabstrupper (3/46).
  • The origin of the WFFS allele remains uncertain. It did not originate from Bairactar Or. Ar as theorized, as evidenced by DNA analysis and the genotypes of 302 Arabians, all of which were homozygous for the reference allele.

Implications

  • The study’s findings suggested that the WFFS allele is moderately frequent and a potential concern in warmbloods, as well as in other breeds where it was not previously expected.
  • The efforts to trace the origin of the WFFS allele remains ongoing given that the Arabian breed, initially considered the source, has been ruled out.
  • This research underscores the need for further investigation to understand the origins and wider impacts of the WFFS allele across horse breeds.

Cite This Article

APA
Reiter S, Wallner B, Brem G, Haring E, Hoelzle L, Stefaniuk-Szmukier M, Długosz B, Piórkowska K, Ropka-Molik K, Malvick J, Penedo MCT, Bellone RR. (2020). Distribution of the Warmblood Fragile Foal Syndrome Type 1 Mutation (PLOD1 c.2032G>A) in Different Horse Breeds from Europe and the United States. Genes (Basel), 11(12). https://doi.org/10.3390/genes11121518

Publication

Genes
ISSN: 2073-4425
NlmUniqueID: 101551097
Country: Switzerland
Language: English
Volume: 11
Issue: 12

Researcher Affiliations

Reiter, Simone
  • Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
Wallner, Barbara
  • Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
Brem, Gottfried
  • Institute of Animal Breeding and Genetics, University of Veterinary Medicine Vienna, 1210 Vienna, Austria.
Haring, Elisabeth
  • Central Research Laboratories, Museum of Natural History, 1010 Vienna, Austria.
  • Department of Evolutionary Biology, University of Vienna, 1090 Vienna, Austria.
Hoelzle, Ludwig
  • Institute of Animal Science, University of Hohenheim, 70599 Stuttgart, Germany.
Stefaniuk-Szmukier, Monika
  • Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Kraków, al. Mickiewicza 24/28, 30-059 Kraków, Poland.
Długosz, Bogusława
  • Department of Animal Reproduction, Anatomy and Genomics, University of Agriculture in Kraków, al. Mickiewicza 24/28, 30-059 Kraków, Poland.
Piórkowska, Katarzyna
  • Department of Animal Molecular Biology, National Research Institute of Animal Production, Krakowska 1, 32-083 Balice, Poland.
Ropka-Molik, Katarzyna
  • Department of Animal Molecular Biology, National Research Institute of Animal Production, Krakowska 1, 32-083 Balice, Poland.
Malvick, Julia
  • Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Penedo, Maria Cecilia T
  • Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Bellone, Rebecca R
  • Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
  • Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.

MeSH Terms

  • Alleles
  • Animals
  • Breeding
  • Datasets as Topic
  • Europe / epidemiology
  • Horse Diseases / epidemiology
  • Horse Diseases / genetics
  • Horses / classification
  • Horses / genetics
  • Mutation, Missense
  • Point Mutation
  • Procollagen-Lysine, 2-Oxoglutarate 5-Dioxygenase / genetics
  • Skin Diseases, Genetic / epidemiology
  • Skin Diseases, Genetic / genetics
  • Skin Diseases, Genetic / veterinary
  • Species Specificity
  • United States / epidemiology

Conflict of Interest Statement

J.M., M.C.T.P., and R.R.B. are affiliated with the UC Davis Veterinary Genetics Laboratory, a genetic testing laboratory offering genetic diagnostic testing in horses and other species.

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Citations

This article has been cited 10 times.
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