Department of Theoretical Bioinformatics, German Cancer Research Center, PO Box 101949, D-69009 Heidelberg, Germany. k.fellenberg@dkfz.de|Department of Theoretical Bioinformatics, German Cancer Research Center, PO Box 101949, D-69009 Heidelberg, Germany. k.fellenberg@dkfz.de|Department of Theoretical Bioinformatics, German Cancer Research Center, PO Box 101949, D-69009 Heidelberg, Germany. k.fellenberg@dkfz.de|Department of Theoretical Bioinformatics, German Cancer Research Center, PO Box 101949, D-69009 Heidelberg, Germany. k.fellenberg@dkfz.de|Department of Theoretical Bioinformatics, German Cancer Research Center, PO Box 101949, D-69009 Heidelberg, Germany. k.fellenberg@dkfz.de