title: Does Sequence Conservation Provide Evidence for Biological Function?
abstract: Finding a signature of purifying selection in a gene is usually interpreted as evidence for the gene providing a function that is targeted by natural selection. This opinion offers a very different hypothesis: purifying selection may be due to removing harmful mutations from the population, that is, the gene and its encoded protein become harmful after a mutation occurred, possibly because the mutated protein interferes with the translation machinery, or because of toxicity of the misfolded protein. Finding a signature of purifying selection should not automatically be considered proof of the gene's selectable function.
authors: Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06269-3125, USA.
authors: Seila
authors: S
authors: Omer
authors: Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06269-3125, USA.
authors: Timothy J
authors: TJ
authors: Harlow
authors: Department of Molecular and Cell Biology, University of Connecticut, 91 North Eagleville Road, Storrs, CT 06269-3125, USA; Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA. Electronic address: gogarten@uconn.edu.
authors: Johann Peter
authors: JP
authors: Gogarten
mesh_terms: D001483:Base Sequence; D017124:Conserved Sequence / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D019143:Evolution, Molecular; D014644:Genetic Variation / Q000235:genetics*; D008957:Models, Genetic; D009154:Mutation / Q000235:genetics; D010802:Phylogeny; D019779:Salmonella enterica / Q000235:genetics*; D012641:Selection, Genetic / Q000235:genetics
keywords: dN/dS; gene transfer agents; phage domestication; prophage; purifying selection; selection for function; selfish gene