Department of Computer Science, Colorado State University, Fort Collins, CO 80526, USA, Department of Computer Science, University of Helsinki, Finland and Bioinformatics Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA.|Department of Computer Science, Colorado State University, Fort Collins, CO 80526, USA, Department of Computer Science, University of Helsinki, Finland and Bioinformatics Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA.|Department of Computer Science, Colorado State University, Fort Collins, CO 80526, USA, Department of Computer Science, University of Helsinki, Finland and Bioinformatics Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA.|Department of Computer Science, Colorado State University, Fort Collins, CO 80526, USA, Department of Computer Science, University of Helsinki, Finland and Bioinformatics Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA.