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bioRxiv · 10.1101/032250

From raw reads to trees: Whole genome SNP phylogenetics across the tree of life

Sanaa Afroz Ahmed·Chien-Chi Lo·Po-E Li·Karen W Davenport·Patrick S.G. Chain
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Abstract

Next-generation sequencing is increasingly being used to examine closely related organisms. However, while genome-wide single nucleotide polymorphisms (SNPs) provide an excellent resource for phylogenetic reconstruction, to date evolutionary analyses have been performed using different ad hoc methods that are not often widely applicable across different projects. To facilitate the construction of robust phylogenies, we have developed a method for genome-wide identification/characterization of SNPs from sequencing reads and genome assemblies. Our phylogenetic and molecular evolutionary (PhaME) analysis software is unique in its ability to take reads and draft/complete genome(s) as input, derive core genome alignments, identify SNPs, construct phylogenies and perform evolutionary analyses. Several examples using genomes and read datasets for bacterial, eukaryotic and viral linages demonstrate the broad and robust functionality of PhaME. Furthermore, the ability to incorporate raw metagenomic reads from clinical samples with suspected infectious agents shows promise for the rapid phylogenetic characterization of pathogens within complex samples.

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Sanaa Afroz Ahmed, Chien-Chi Lo, Po-E Li, Karen W Davenport, Patrick S.G. Chain. 2015-11-19. From raw reads to trees: Whole genome SNP phylogenetics across the tree of life. https://doi.org/10.1101/032250

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