Bioinformatics, Institute of Computer Science, University of Freiburg, Freiburg, Germany. schmiedc@informatik.uni-freiburg.de.|Bioinformatics, Institute of Computer Science, University of Freiburg, Freiburg, Germany. mamo181@googlemail.com.|Max Planck Institute of Immunobiology and Epigenetics, Stuebeweg 51, Freiburg, 79108, Germany. heyne@informatik.uni-freiburg.de.|Department of Computer Science, University of Haifa, Mount Carmel, Haifa, Israel. mika.amit2@gmail.com.|Department of Computer Science, University of Haifa, Mount Carmel, Haifa, Israel. landau@univ.haifa.ac.il.|Bioinformatics, Institute of Computer Science, University of Freiburg, Freiburg, Germany. backofen@informatik.uni-freiburg.de.|Bioinformatics, Institute of Computer Science, University of Freiburg, Freiburg, Germany. swill@csail.mit.edu.