Higher quality de novo genome assemblies from degraded museum specimens: a linked-read approach to museomics

Colella, J. P.; Tigano, A.; MacManes, M.

doi:10.1101/716506

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bioRxiv · 10.1101/716506

Higher quality de novo genome assemblies from degraded museum specimens: a linked-read approach to museomics

Colella, J. P.·Tigano, A.·MacManes, M.

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Abstract

AO_SCPLOWBSTRACTC_SCPLOWHigh-throughput sequencing technologies are a proposed solution for accessing the molecular data in historic specimens. However, degraded DNA combined with the computational demands of short-read assemblies has posed significant laboratory and bioinformatics challenges. Linked-read or synthetic long-read sequencing technologies, such as 10X Genomics, may provide a cost-effective alternative solution to assemble higher quality de novo genomes from degraded specimens. Here, we compare assembly quality (e.g., genome contiguity and completeness, presence of orthogroups) between four published genomes assembled from a single shotgun library and four deer mouse (Peromyscus spp.) genomes assembled using 10X Genomics technology. At a similar price-point, these approaches produce vastly different assemblies, with linked-read assemblies having overall higher quality, measured by larger N50 values and greater gene content. Although not without caveats, our results suggest that linked-read sequencing technologies may represent a viable option to build de novo genomes from historic museum specimens, which may prove particularly valuable for extinct, rare, or difficult to collect taxa.

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Colella, J. P., Tigano, A., MacManes, M.. 2019-07-28. Higher quality de novo genome assemblies from degraded museum specimens: a linked-read approach to museomics. https://doi.org/10.1101/716506

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