Alvira: comparative genomics of viral strains.

MOTIVATION: The Alvira tool is a general purpose multiple sequence alignment viewer with a special emphasis on the comparative analysis of viral genomes. This new tool has been devised specifically to address the problem of the simultaneous analysis of a large number of viral strains. The multiple alignment is embedded in a graph that can be explored at different levels of resolution. AVAILABILITY: The Alvira software is available at: http://bioinfo.genopole-toulouse.prd.fr/Alvira. SUPPLEMENTARY INFORMATION: A tutorial is available at Alvira's homepage.