Deep sampling of Hawaiian Caenorhabditis elegans reveals high genetic diversity and admixture with global populations
- Northwestern University, United States
- New York University, United States
Abstract
Hawaiian isolates of the nematode species Caenorhabditis elegans have long been known to harbor genetic diversity greater than the rest of the worldwide population, but this observation was supported by only a small number of wild strains. To better characterize the niche and genetic diversity of Hawaiian C. elegans and other Caenorhabditis species, we sampled different substrates and niches across the Hawaiian islands. We identified hundreds of new Caenorhabditis strains from known species and a new species, Caenorhabditis oiwi. Hawaiian C. elegans are found in cooler climates at high elevations but are not associated with any specific substrate, as compared to other Caenorhabditis species. Surprisingly, admixture analysis revealed evidence of shared ancestry between some Hawaiian and non-Hawaiian C. elegans isolates. We suggest that the deep diversity we observed in Hawaii might represent patterns of ancestral genetic diversity in the C. elegans species before human influence.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data are provided for all Figures.
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Funding
No external funding was received for this work.
Reviewing Editor
- Graham Coop, University of California, Davis, United States
Version history
- Received: July 23, 2019
- Accepted: December 2, 2019
- Accepted Manuscript published: December 3, 2019 (version 1)
- Version of Record published: December 23, 2019 (version 2)
Copyright
© 2019, Crombie et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Deep sampling of Hawaiian Caenorhabditis elegans reveals high genetic diversity and admixture with global populations
eLife 8:e50465.
https://doi.org/10.7554/eLife.50465
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