Updated site concordance factors minimize effects of homoplasy and taxon sampling.
Ontology highlight
ABSTRACT: Motivation
Site concordance factors (sCFs) have become a widely used way to summarize discordance in phylogenomic datasets. However, the original version of sCFs was calculated by sampling a quartet of tip taxa and then applying parsimony-based criteria for discordance. This approach has the potential to be strongly affected by multiple hits at a site (homoplasy), especially when substitution rates are high or taxa are not closely related.Results
Here, we introduce a new method for calculating sCFs. The updated version uses likelihood to generate probability distributions of ancestral states at internal nodes of the phylogeny. By sampling from the states at internal nodes adjacent to a given branch, this approach substantially reduces-but does not abolish-the effects of homoplasy and taxon sampling.Availability and implementation
Updated sCFs are implemented in IQ-TREE 2.2.2. The software is freely available at https://github.com/iqtree/iqtree2/releases.Supplementary information
Supplementary information is available at Bioinformatics online.
SUBMITTER: Mo YK
PROVIDER: S-EPMC9805551 | biostudies-literature | 2023 Jan
REPOSITORIES: biostudies-literature
Publications
Updated site concordance factors minimize effects of homoplasy and taxon sampling.
Mo Yu K YK Lanfear Robert R Hahn Matthew W MW Minh Bui Quang BQ
Bioinformatics (Oxford, England) 20230101 1
<h4>Motivation</h4>Site concordance factors (sCFs) have become a widely used way to summarize discordance in phylogenomic datasets. However, the original version of sCFs was calculated by sampling a quartet of tip taxa and then applying parsimony-based criteria for discordance. This approach has the potential to be strongly affected by multiple hits at a site (homoplasy), especially when substitution rates are high or taxa are not closely related.<h4>Results</h4>Here, we introduce a new method f ...[more]
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