Genome similarities between plant and animal RNA viruses.

Gene sequence comparisons and protein comparisons provide more and more evidence that evolutionary links exist between plant and animal RNA viruses, irrespective of whether they have an isometric or rod-shaped particle, or of whether they have a divided or non-divided genome. Although a phylogeny based on these molecular data cannot yet be constructed the results obtained so far shed a new light on the origin and evolution of RNA viruses and are important in terms of their taxonomy.