Article

Effect of site-specific heterogeneous evolution on phylogenetic reconstruction: a simple evaluation.

Institute of Biomedical Sciences, Fudan University, Shanghai 200433, China.
Gene (Impact Factor: 2.2). 09/2008; 441(1-2):156-62. DOI: 10.1016/j.gene.2008.08.003
Source: PubMed

ABSTRACT Recent studies have shown that heterogeneous evolution may mislead phylogenetic analysis, which has been neglected for a long time. We evaluate the effect of heterogeneous evolution on phylogenetic analysis, using 18 fish mitogenomic coding sequences as an example. Using the software DIVERGE, we identify 198 amino acid sites that have experienced heterogeneous evolution. After removing these sites, the rest of sites are shown to be virtually homogeneous in the evolutionary rate. There are some differences between phylogenetic trees built with heterogeneous sites ("before tree") and without heterogeneous sites ("after tree"). Our study demonstrates that for phylogenetic reconstruction, an effective approach is to identify and remove sites with heterogeneous evolution, and suggests that researchers can use the software DIVERGE to remove the influence of heterogeneous evolution before reconstructing phylogenetic trees.

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