Bioinformatics Group, Department of Computer Science, University of Leipzig Härtelstrasse 16-18, D-04107 Leipzig, Germany.|Bioinformatics Group, Department of Computer Science, University of Leipzig Härtelstrasse 16-18, D-04107 Leipzig, Germany.|Bioinformatics Group, Department of Computer Science, University of Leipzig Härtelstrasse 16-18, D-04107 Leipzig, Germany.