title: Rates of genomic divergence in humans, chimpanzees and their lice.
abstract: The rate of DNA mutation and divergence is highly variable across the tree of life. However, the reasons underlying this variation are not well understood. Comparing the rates of genetic changes between hosts and parasite lineages that diverged at the same time is one way to begin to understand differences in genetic mutation and substitution rates. Such studies have indicated that the rate of genetic divergence in parasites is often faster than that of their hosts when comparing single genes. However, the variation in this relative rate of molecular evolution across different genes in the genome is unknown. We compared the rate of DNA sequence divergence between humans, chimpanzees and their ectoparasitic lice for 1534 protein-coding genes across their genomes. The rate of DNA substitution in these orthologous genes was on average 14 times faster for lice than for humans and chimpanzees. In addition, these rates were positively correlated across genes. Because this correlation only occurred for substitutions that changed the amino acid, this pattern is probably produced by similar functional constraints across the same genes in humans, chimpanzees and their ectoparasites.
authors.affiliation: Illinois Natural History Survey, University of Illinois, , 1816 South Oak Street, Champaign, IL 61820, USA, Department of Animal Biology, University of Illinois, , Urbana, IL 61801, USA, Department of Entomology, University of Illinois, , Urbana, IL 61801, USA, Department of Biology Sciences, University of Notre Dame, , Notre Dame, IN 46556, USA, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, , Kampala, Uganda, College of Veterinary Medicine, University of Minnesota, , St. Paul, MN 55108, USA, Conservation and Ecosystem Health Alliance, , Kampala, Uganda, Florida Museum of Natural History, University of Florida, , Gainesville, FL 32611, USA.
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Johnson
authors.forename: Julie M
authors.initials: JM
authors.lastname: Allen
authors.forename: Brett P
authors.initials: BP
authors.lastname: Olds
authors.forename: Lawrence
authors.initials: L
authors.lastname: Mugisha
authors.forename: David L
authors.initials: DL
authors.lastname: Reed
authors.forename: Ken N
authors.initials: KN
authors.lastname: Paige
authors.forename: Barry R
authors.initials: BR
authors.lastname: Pittendrigh
mesh_terms: D000818:Animals; D019143:Evolution, Molecular; D005260:Female; D054629:Genome, Mitochondrial; D006801:Humans; D008969:Molecular Sequence Data; D002679:Pan troglodytes / Q000235:genetics* / Q000469:parasitology*; D010374:Pediculus / Q000235:genetics / Q000502:physiology*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014454:Uganda
keywords: Pediculus; coevolution; genomics; hosts and parasites; molecular evolution