Swiss Institute of Bioinformatics , Centre Médical Universitaire, 1211 Geneva 4, Switzerland. anais.mottaz@isb-sib.ch|Swiss Institute of Bioinformatics , Centre Médical Universitaire, 1211 Geneva 4, Switzerland. anais.mottaz@isb-sib.ch|Swiss Institute of Bioinformatics , Centre Médical Universitaire, 1211 Geneva 4, Switzerland. anais.mottaz@isb-sib.ch|Swiss Institute of Bioinformatics , Centre Médical Universitaire, 1211 Geneva 4, Switzerland. anais.mottaz@isb-sib.ch