In association with CEA-Genoscope and the Sanger Institute, scientists at the Institut Pasteur in Paris, the CNRS, INSERM, the Institut Pasteur of Lille, and Université Lille 2 have recently determined the origin of the emergence of the Mycobacterium tuberculosis bacterium, the main causative agent of tuberculosis. Researchers have also provided insights into its evolutionary success. They have identified several genetic mechanisms that could have contributed to the worldwide dissemination of this pathogen, which currently infects up to 2 billion people.