[1
] Méthodes et Algorithmes pour la Bioinformatique, LIRMM, CNRS, Université de Montpellier,
34392 Montpellier Cedex 5, France
[2
] Department of Statistics, University of Auckland, Auckland 1142, New Zealand
[3
] Institute of Computational Science, ETH, CH-8092 Zurich, Switzerland
[4
] Swiss Institute of Bioinformatics, CH-1015 Lausanne, Switzerland
[5
] Department of Statistics, University of Oxford, OX1 3TG Oxford, UK