Résumé
This paper investigates the problem of conservation of combinatorial structures in genome rearrangement scenarios. We give a characterization of a class of scenarios that conserve all common intervals, called commuting scenarios, and a characterization of permutations for which commuting scenarios exist. We show that measuring conservation of common intervals can be useful tool in assessing the quality of rearrangement scenarios, by investigating in detail three specific scenarios involving the mouse, rat and human X chromosomes.