Selfish operons: horizontal transfer may drive the evolution of gene clusters.

  title={Selfish operons: horizontal transfer may drive the evolution of gene clusters.},
  author={Jeffrey G. Lawrence and John R. Roth},
  volume={143 4},
A model is presented whereby the formation of gene clusters in bacteria is mediated by transfer of DNA within and among taxa. Bacterial operons are typically composed of genes whose products contribute to a single function. If this function is subject to weak selection or to long periods with no selection, the contributing genes may accumulate mutations and be lost by genetic drift. From a cell's perspective, once several genes are lost, the function can be restored only if all missing genes… 

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