Phylogenetic analysis and gene functional predictions: phylogenomics in action

Making accurate functional predictions for genes is a key step in this era of high throughput gene and genome sequencing. While most functional prediction methods are comparative in nature, many do not take advantage of the power that an evolutionary perspective provides to any comparative biology analysis. Here we review how evolutionary analysis can greatly benefit both homology-based and non-homology-based functional prediction methods. Examples that are discussed include phylogenetic determination of orthology, the use of character state reconstruction analysis of gene function, and evolutionary analysis of rates and patterns of gene evolution.