HGT: Genome-Scale Estimates of Horizontal Gene Transfer

PLoS Biology: The Cobweb of Life Revealed by Genome-Scale Estimates of Horizontal Gene Transfer: "The role of horizontal gene transfer (HGT) in speciation, adaptation, and evolution of life on earth has been studied intensively [1], and there has been a growing body of evidence of transfers of genes among species [2�4] and transfers from organelles to nuclei [5�7]. Whole genome analyses of different prokaryotes have been thought to indicate rampant HGTs [8,9] and suggest that HGT plays a pivotal role in prokaryotic evolution, producing dynamic and mosaic genomes. The speculation [10] that even genes involved in transcription and translation might have been subject to HGT has also led to the suggestion that HGT should be considered the essence of phylogeny and that HGT might have eroded the organismal genealogical trace. Therefore, life history cannot be properly represented by the traditional treelike form, but rather by a netlike form [4,11�13]."