ZBH - Center for Bioinformatics, University of Hamburg, Bundesstrasse 43, 20146 Hamburg, Germany. dellinghaus@zbh.uni-hamburg.de|ZBH - Center for Bioinformatics, University of Hamburg, Bundesstrasse 43, 20146 Hamburg, Germany. dellinghaus@zbh.uni-hamburg.de|ZBH - Center for Bioinformatics, University of Hamburg, Bundesstrasse 43, 20146 Hamburg, Germany. dellinghaus@zbh.uni-hamburg.de