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bioRxiv · 10.1101/428870

Fast genetic mapping of complex traits in C. elegans using millions of individuals in bulk

Burga, A.·Ben-David, E.·Lemus Vergara, T.·Boocock, J.·Kruglyak, L.
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Abstract

Genetic studies of complex traits in animals have been hindered by the need to generate, maintain, and phenotype large panels of recombinant lines. We developed a new method, C. elegans eXtreme Quantitative Trait Locus (ceX-QTL) mapping, that overcomes this obstacle via bulk selection on millions of unique recombinant individuals. We used ceX-QTL to map a drug resistance locus with high resolution. We also mapped differences in gene expression in live worms and discovered a regulatory feedback loop that responds to changes in HSP-90 chaperone activity. Lastly, we used ceX-QTL to map loci that influence fitness and discovered that one such locus is caused by a deletion in a highly conserved chromatin reader in the N2 reference strain. ceX-QTL is fast, powerful and cost-effective, and will accelerate the study of complex traits in animals.

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Burga, A., Ben-David, E., Lemus Vergara, T., Boocock, J., Kruglyak, L.. 2018-09-27. Fast genetic mapping of complex traits in C. elegans using millions of individuals in bulk. https://doi.org/10.1101/428870

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