1 Biocomputing Group, FABIT-University of Bologna, Italy.
2 Institute of Clinical Sciences, Faculty of Medicine. Imperial College London, Hammersmith Campus, Du Cane Road, London W12 0NN, UK; Computational Regulatory Genomics, MRC London Institute of Medical Sciences, Du Cane Road, London W12 0NN, UK.
3 Structural Bioinformatics Group, Centre for Integrative Systems Biology and Bioinformatics, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK. Electronic address: m.sternberg@imperial.ac.uk.