Inferring Nonneutral Evolution from Human-Chimp-Mouse Orthologous Gene Trios

摘要: Even though human and chimpanzee gene sequences are nearly 99% identical, sequence comparisons can nevertheless be highly informative in identifying biologically important changes that have occurred since our ancestral lineages diverged. We analyzed alignments of 7645 to their mouse orthologs. These three-species allowed us identify genes undergoing natural selection along the chimp lineage by fitting models include parameters specifying rates synonymous nonsynonymous nucleotide substitution. This evolutionary approach revealed an set with significantly different patterns substitution on compared lineages. Partitions into inferred biological classes identified accelerated evolution several functional classes, including olfaction nuclear transport. In addition suggesting adaptive physiological differences between chimps humans, human-accelerated more likely underlie major known Mendelian disorders.