Article open access publication

Evolutionary Genomics and Conservation of the Endangered Przewalski’s Horse

Current Biology, Elsevier, ISSN 1879-0445

Volume 25, 19, 2015

DOI:10.1016/j.cub.2015.08.032, Dimensions: pub.1051323049, PMC: PMC5104162, PMID: 26412128,

Affiliations

Organisations

  1. (1) University of Copenhagen, grid.5254.6, KU
  2. (2) University of California, Berkeley, grid.47840.3f
  3. (3) University College London, grid.83440.3b
  4. (4) Hebrew University of Jerusalem, grid.9619.7
  5. (5) Technical University of Denmark, grid.5170.3, DTU
  6. (6) Pompeu Fabra University, grid.5612.0
  7. (7) San Diego Zoo Institute for Conservation Research, grid.452788.4
  8. (8) Agroscope, grid.417771.3
  9. (9) University of Bern, grid.5734.5
  10. (10) Tour du Valat, grid.452794.9
  11. (11) Leibniz Institute for Zoo and Wildlife Research, grid.418779.4
  12. (12) Zoological Institute, grid.439287.3
  13. (13) EAZA Equid TAG, Köln 50668, Germany
  14. (14) Martin Luther University Halle-Wittenberg, grid.9018.0
  15. (15) North-Eastern Federal University, grid.440700.7
  16. (16) Centro Nacional de Análisis Genómico, grid.452341.5
  17. (17) University of Minnesota, grid.17635.36
  18. (18) Université de Toulouse, University Paul Sabatier (UPS), Laboratoire AMIS, CNRS UMR 5288, 37 Allées Jules Guesde, 31000 Toulouse, France

Description

Przewalski's horses (PHs, Equus ferus ssp. przewalskii) were discovered in the Asian steppes in the 1870s and represent the last remaining true wild horses. PHs became extinct in the wild in the 1960s but survived in captivity, thanks to major conservation efforts. The current population is still endangered, with just 2,109 individuals, one-quarter of which are in Chinese and Mongolian reintroduction reserves [1]. These horses descend from a founding population of 12 wild-caught PHs and possibly up to four domesticated individuals [2-4]. With a stocky build, an erect mane, and stripped and short legs, they are phenotypically and behaviorally distinct from domesticated horses (DHs, Equus caballus). Here, we sequenced the complete genomes of 11 PHs, representing all founding lineages, and five historical specimens dated to 1878-1929 CE, including the Holotype. These were compared to the hitherto-most-extensive genome dataset characterized for horses, comprising 21 new genomes. We found that loci showing the most genetic differentiation with DHs were enriched in genes involved in metabolism, cardiac disorders, muscle contraction, reproduction, behavior, and signaling pathways. We also show that DH and PH populations split ∼45,000 years ago and have remained connected by gene-flow thereafter. Finally, we monitor the genomic impact of ∼110 years of captivity, revealing reduced heterozygosity, increased inbreeding, and variable introgression of domestic alleles, ranging from non-detectable to as much as 31.1%. This, together with the identification of ancestry informative markers and corrections to the International Studbook, establishes a framework for evaluating the persistence of genetic variation in future reintroduced populations.

Funders

Research Categories

Main Subject Area

Fields of Research

Links & Metrics

NORA University Profiles

University of Copenhagen

Technical University of Denmark

Danish Open Access Indicator

2015: Blocked

Research area: Science & Technology

Danish Bibliometrics Indicator

2015: Level 2

Research area: Science & Technology

Dimensions Citation Indicators

Times Cited: 93

Field Citation Ratio (FCR): 12.46

Relative Citation ratio (RCR): 4.18

Open Access Info

Hybrid