Weir W. auteur aut IRD Capewell P. auteur aut IRD Foth B. auteur aut IRD Clucas C. auteur aut IRD Pountain A. auteur aut IRD Steketee P. auteur aut IRD Veitch N. auteur aut IRD Koffi M. auteur aut IRD De Meeûs Thierry auteur aut IRD Kabore J. auteur aut IRD Camara M. auteur aut IRD Cooper A. auteur aut IRD Tait A. auteur aut IRD Jamonneau Vincent auteur aut IRD Bucheton Bruno auteur aut IRD Berriman M. auteur aut IRD MacLeod A. auteur aut IRD text journalArticle eng text/pdf reformatted digital access Evolutionary theory predicts that the lack of recombination and chromosomal re assortment in strictly asexual organisms results in homologous chromosomes irreversibly accumulating mutations and thus evolving independently of each other, a phenomenon termed the Meselson effect. We apply a population genomics approach to examine this effect in an important human pathogen, Trypanosoma brucei gambiense. We determine that T.b. gambiense is evolving strictly asexually and is derived from a single progenitor, which emerged within the last 10,000 years. We demonstrate the Meselson effect for the first time at the genome-wide level in any organism and show large regions of loss of heterozygosity, which we hypothesise to be a short-term compensatory mechanism for counteracting deleterious mutations. Our study sheds new light on the genomic and evolutionary consequences of strict asexuality, which this pathogen uses as it exploits a new biological niche, the human population. specialized AFRIQUE DE L'OUEST CAMEROUN GUINEE COTE D'IVOIRE 052 020 5 e11473 [14 p.] 2016 2050-084X https://www.documentation.ird.fr/hor/fdi:010066155 10.7554/eLife.11473 2050-084X [F B010066155] https://www.documentation.ird.fr/hor/fdi:010066155 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers16-02/010066155.pdf IRD - Base Horizon / Pleins textes 2016-02-26 2017-08-23 fdi:010066155 fre