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bioRxiv · 10.1101/2022.12.05.519109

Uncovering the genomic basis of infection through co-genomic sequencing of hosts and parasites

Dexter, E.·Fields, P.·Ebert, D.
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Abstract

Understanding the genomic basis of infectious disease is fundamental objective in coevolutionary theory with relevance to healthcare, agriculture, and epidemiology. Models of host-parasite coevolution often assume that infection requires specific combinations of host and parasite genotypes. Coevolving host and parasite loci are therefor expected to show associations that reflects an underlying infection/resistance allele matrix, yet little evidence for such genome-to-genome interactions has been observed among natural populations. We conducted a study to search for this genomic signature across 258 linked host (Daphnia magna) and parasite (Pasteuria ramosa) genomes. Our results show a clear signal of genomic association between multiple epistatically-interacting loci in the host genome, and a family of genes encoding for collagen-like protein in the parasite genome. These findings are supported by laboratory-based infection trials, which show strong correspondence between phenotype and genotype at the identified loci. Our study provides clear genomic evidence of antagonistic coevolution among wild populations.

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Dexter, E., Fields, P., Ebert, D.. 2022-12-08. Uncovering the genomic basis of infection through co-genomic sequencing of hosts and parasites. https://doi.org/10.1101/2022.12.05.519109

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