Tuberculosis: discovery of an ancestral lineage in the African Great Lakes region

Two exceptional strains of tuberculosis, isolated from East African patients with multi-resistant forms of the disease, have been discovered thanks to the use of a new molecular test, Deeplex-MycTB1 . These strains belong to a so far unknown bacterial lineage, apparently limited to the African Great Lakes region. Genome analyses show that this lineage originated from an ancestral phylum which predates the branching point shared by all other lineages of common tuberculosis strains known to date. This discovery reinforces the hypothesis of an East African origin for the tuberculosis bacillus, which remains the main cause of death from infectious causes, and provides additional molecular clues about the evolution towards a pathogenic lifestyle. This work, carried out by an international team led by researchers from the Lille Centre for Infection and Immunity (CNRS/Inserm/Institut Pasteur de Lille/Université de Lille/CHU de Lille), is published on June 9th 2020 in Nature Communications.

• 1Deeplex-MycTB is an antibiotic resistance prediction test for Mycobacterium tuberculosis developed by GenoScreen in collaboration with Dr Philip Supply.