||Segmental duplication has long been known to be an important mechanism for genome growth and evolution . Beyond that, recent study has spotted occurrence of whole-genome duplication on yeast . In this work we investigate possible association of inverse symmetry with origin sites and terminal sites on genomes. Our findings, through analyses of word-frequency nucleotides and distributions of homologous genes on publicly available complete genomes of 18 archaea and 140 bacteria, are positive. These findings suggest, first, that whole-genome inverse duplications have occurred in most prokaryotic chromosomes near original sites and terminal sites. Secondly, inverse symmetry can be taken as a feature to predict loci of original sites and terminal sites in prokaryotic chromosomes. Thirdly, prokaryotic organisms can be classified into four categories by diversity of inverse symmetry in prokaryotic chromosomes. Phylogeny and taxonomy among the four categories have also been investigated.|
|| Lynch M. Genomics. Gene duplication and evolution. (2002) Science 297:945-7.|
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