The salmon louse genome may be much larger than sequencing suggests
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Abstract
The genome size of organisms impacts their evolution and biology and is often assumed to be characteristic of a species. Here we present the first published estimates of genome size of the ecologically and economically important ectoparasite, Lepeophtheirus salmonis (Copepoda, Caligidae). Four independent L. salmonis genome assemblies of the North Atlantic subspecies Lepeophtheirus salmonis salmonis , including two chromosome level assemblies, yield assemblies ranging from 665 – 790 Mbps. These genome assemblies are congruent in their findings, and appear very complete with Benchmarking Universal Single-Copy Orthologs analyses finding >92% of expected genes and transcriptome datasets routinely mapping >90% of reads. However, two cytometric techniques, flow cytometry and Feulgen image analysis densitometry, yield measurements of 1.3-1.6 Gb in the haploid genome. Interestingly, earlier cytometric measurements reported genome sizes of 939 and 567 Mbps in L. salmonis salmonis samples from Bay of Fundy and Norway, respectively. Available data thus suggest that the genome sizes of salmon lice are variable. Current understanding of eukaryotic genome dynamics suggests that the most likely explanation for such variability involves repetitive DNA, which for L. salmonis makes up ≈60% of the genome assemblies.Keywords
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- Published version: Scientific Reports, 12 (1), 1.
This publication has 68 references indexed in Scilit:
- Salmon lice – impact on wild salmonids and salmon aquacultureJournal of Fish Diseases, 2013
- Repetitive DNA and next-generation sequencing: computational challenges and solutionsNature Reviews Genetics, 2011
- A fast, lock-free approach for efficient parallel counting of occurrences of k-mersBioinformatics, 2011
- Establishment and characterisation of salmon louse (Lepeophtheirus salmonis (Krøyer 1837)) laboratory strainsParasitology International, 2009
- Fast and accurate short read alignment with Burrows–Wheeler transformBioinformatics, 2009
- EST and Mitochondrial DNA Sequences Support a Distinct Pacific Form of Salmon Louse, Lepeophtheirus salmonisMarine Biotechnology, 2008
- Cis-Regulatory Elements in the Accord Retrotransposon Result in Tissue-Specific Expression of the Drosophila melanogaster Insecticide Resistance Gene Cyp6g1Genetics, 2007
- Genome sizes of cyclopoid copepods (Crustacea): evidence of evolutionary constraintBiological Journal of the Linnean Society, 2006
- Innate and acquired variation of nuclear DNA contents of marine copepodsGenome, 1992
- Similar nucleus numbers among copepodsCanadian Journal of Zoology, 1983