Computational Biology Unit, Bergen Center for Computational Science, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway. sivh@ii.uib.no|Computational Biology Unit, Bergen Center for Computational Science, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway. sivh@ii.uib.no|Computational Biology Unit, Bergen Center for Computational Science, University of Bergen, Thormøhlensgt. 55, N-5008 Bergen, Norway. sivh@ii.uib.no