contrasted patterns of selection on mhc-linked microsatellites in natural populations of the malagasy plague reservoir对比的模式选择上mhc-linked微卫星在马达加斯加瘟疫水库的自然种群.pdf

Contrasted Patterns of Selection on MHC-Linked Microsatellites in Natural Populations of the Malagasy Plague Reservoir 1 1 1 2 3 Charlotte Tollenaere , Svilena Ivanova , Jean-Marc Duplantier , Anne Loiseau , Lila Rahalison , 3 1 Soanandrasana Rahelinirina , Carine Brouat * ´ 1 Institut de Recherche pour le Developpement, UMR CBGP (INRA/IRD/Cirad/Montpellier SupAgro), Montferrier sur Lez, France, 2 Institut National de la Recherche ´ Agronomique, UMR CBGP (INRA/IRD/Cirad/Montpellier SupAgro), Montferrier sur Lez, France, 3 Institut Pasteur de Madagascar, Unite Peste, Antananarivo, Madagascar Abstract Plague (Yersinia pestis infection) is a highly virulent rodent disease that persists in many natural ecosystems. The black rat (Rattus rattus) is the main host involved in the plague focus of the central highlands of Madagascar. Black rat populations from this area are highly resistant to plague, whereas those from areas in which the disease is absent (low altitude zones of Madagascar) are susceptible. Various lines of evidence suggest a role for the Major Histocompatibility Complex (MHC) in plague resistance. We therefore used the MHC region as a candidate for detecting signatures of plague-mediated selection in Malagasy black rats, by comparing population genetic structures for five MHC-linked microsatellites and neutral markers in two sampling designs. We first compared four pairs of populations, each pair including one population from the plague focus and one from the disease-fr