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Scientific reports2021; 11(1); 16057; doi: 10.1038/s41598-021-95669-1

Rare and common variant discovery by whole-genome sequencing of 101 Thoroughbred racehorses.

Abstract: The Thoroughbred breed was formed by crossing Oriental horse breeds and British native horses and is currently used in horseracing worldwide. In this study, we constructed a single-nucleotide variant (SNV) database using data from 101 Thoroughbred racehorses. Whole genome sequencing (WGS) revealed 11,570,312 and 602,756 SNVs in autosomal (1-31) and X chromosomes, respectively, yielding a total of 12,173,068 SNVs. About 6.9% of identified SNVs were rare variants observed only in one allele in 101 horses. The number of SNVs detected in individual horses ranged from 4.8 to 5.3 million. Individual horses had a maximum of 25,554 rare variants; several of these were functional variants, such as non-synonymous substitutions, start-gained, start-lost, stop-gained, and stop-lost variants. Therefore, these rare variants may affect differences in traits and phenotypes among individuals. When observing the distribution of rare variants among horses, one breeding stallion had a smaller number of rare variants compared to other horses, suggesting that the frequency of rare variants in the Japanese Thoroughbred population increases through breeding. In addition, our variant database may provide useful basic information for industrial applications, such as the detection of genetically modified racehorses in gene-doping control and pedigree-registration of racehorses using SNVs as markers.
Publication Date: 2021-08-06 PubMed ID: 34362995PubMed Central: PMC8346562DOI: 10.1038/s41598-021-95669-1Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

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The research article focuses on the discovery of rare and common genetic variations in Thoroughbred racehorses using whole-genome sequencing. It indicates that these genetic differences could influence variations in traits and phenotypes among individual horses.

Primary Objectives and Methods

  • The primary aim of the research was to construct a single-nucleotide variant (SNV) database using data from 101 Thoroughbred racehorses. SNVs are small scale genetic alterations, and their study provides valuable insights into individual genetic differences among organisms.
  • The researchers used whole-genome sequencing (WGS), a process that allows the detailed mapping of every gene in an organism’s genome, to detect these SNVs.

Key Findings

  • From the 101 Thoroughbred racehorses, a total of 12,173,068 SNVs were identified. Of these, about 6.9% were rare variants, which only appeared in one allele in the 101 horses.
  • The number of SNVs detected in individual horses ranged from approximately 4.8 to 5.3 million.
  • Each horse had a maximum of 25,554 rare variants. Some of these were functional variants, such as non-synonymous substitutions, start-gained, start-lost, stop-gained, and stop-lost variants. These could potentially affect the differences in traits and phenotypes among the horses.
  • The researchers found that one breeding stallion had a smaller number of rare variants compared to other horses. This suggests that the frequency of rare variants in the Japanese Thoroughbred population might increase through breeding.

Implications and Applications

  • The SNV database created in this study could prove vital for a range of applications in the equine industry. It could be used for the detection of genetically modified racehorses in gene-doping control, which is the practice of using genetic modification to enhance the performance of horses.
  • In addition, it could be useful for pedigree-registration of racehorses, using SNVs as markers. This would allow for the precise tracing of a horse’s lineage, which is valuable for breeders and racehorse owners.

Cite This Article

APA
Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Kusano K, Nagata SI. (2021). Rare and common variant discovery by whole-genome sequencing of 101 Thoroughbred racehorses. Sci Rep, 11(1), 16057. https://doi.org/10.1038/s41598-021-95669-1

Publication

ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 11
Issue: 1
Pages: 16057
PII: 16057

Researcher Affiliations

Tozaki, Teruaki
  • Genetic Analysis Department, Laboratory of Racing Chemistry, 1731-2, Tsurutamachi, Utsunomiya, Tochigi, 320-0851, Japan. ttozaki@lrc.or.jp.
  • Equine Department, Japan Racing Association, 6-11-1, Roppongi, Minato, Tokyo, 106-8401, Japan. ttozaki@lrc.or.jp.
Ohnuma, Aoi
  • Genetic Analysis Department, Laboratory of Racing Chemistry, 1731-2, Tsurutamachi, Utsunomiya, Tochigi, 320-0851, Japan.
Kikuchi, Mio
  • Genetic Analysis Department, Laboratory of Racing Chemistry, 1731-2, Tsurutamachi, Utsunomiya, Tochigi, 320-0851, Japan.
Ishige, Taichiro
  • Genetic Analysis Department, Laboratory of Racing Chemistry, 1731-2, Tsurutamachi, Utsunomiya, Tochigi, 320-0851, Japan.
Kakoi, Hironaga
  • Genetic Analysis Department, Laboratory of Racing Chemistry, 1731-2, Tsurutamachi, Utsunomiya, Tochigi, 320-0851, Japan.
Hirota, Kei-Ichi
  • Genetic Analysis Department, Laboratory of Racing Chemistry, 1731-2, Tsurutamachi, Utsunomiya, Tochigi, 320-0851, Japan.
Kusano, Kanichi
  • Equine Department, Japan Racing Association, 6-11-1, Roppongi, Minato, Tokyo, 106-8401, Japan.
Nagata, Shun-Ichi
  • Genetic Analysis Department, Laboratory of Racing Chemistry, 1731-2, Tsurutamachi, Utsunomiya, Tochigi, 320-0851, Japan.

MeSH Terms

  • Animals
  • Breeding
  • Female
  • Genotype
  • Horses / genetics
  • Horses / physiology
  • Male
  • Pedigree
  • Phenotype
  • Polymorphism, Single Nucleotide
  • Whole Genome Sequencing / methods

Conflict of Interest Statement

The authors declare no competing interests.

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Citations

This article has been cited 5 times.
  1. Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Takahashi Y, Nagata SI. Short Insertion and Deletion Discoveries via Whole-Genome Sequencing of 101 Thoroughbred Racehorses.. Genes (Basel) 2023 Mar 3;14(3).
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  2. Yokomori T, Ohnuma A, Tozaki T, Segawa T, Itou T. Identification of Personality-Related Candidate Genes in Thoroughbred Racehorses Using a Bioinformatics-Based Approach Involving Functionally Annotated Human Genes.. Animals (Basel) 2023 Feb 20;13(4).
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  3. Suminda GGD, Ghosh M, Son YO. The Innovative Informatics Approaches of High-Throughput Technologies in Livestock: Spearheading the Sustainability and Resiliency of Agrigenomics Research.. Life (Basel) 2022 Nov 15;12(11).
    doi: 10.3390/life12111893pubmed: 36431028google scholar: lookup
  4. Tozaki T, Ohnuma A, Nakamura K, Hano K, Takasu M, Takahashi Y, Tamura N, Sato F, Shimizu K, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Hamilton NA, Nagata SI. Detection of Indiscriminate Genetic Manipulation in Thoroughbred Racehorses by Targeted Resequencing for Gene-Doping Control.. Genes (Basel) 2022 Sep 4;13(9).
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  5. Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Kusano K, Nagata SI. Design and storage stability of reference materials for microfluidic quantitative PCR-based equine gene doping tests.. J Equine Sci 2021 Dec;32(4):125-134.
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