title: Seeking signatures of reinforcement at the genetic level: a hitchhiking mapping and candidate gene approach in the house mouse.
abstract: Reinforcement is the process by which prezygotic isolation is strengthened as a response to selection against hybridization. Most empirical support for reinforcement comes from the observation of its possible phenotypic signature: an accentuated degree of prezygotic isolation in the hybrid zone as compared to allopatry. Here, we implemented a novel approach to this question by seeking for the signature of reinforcement at the genetic level. In the house mouse, selection against hybrids and enhanced olfactory-based assortative mate preferences are observed in a hybrid zone between the two European subspecies Mus musculus musculus and M. m. domesticus, suggesting a possible recent reinforcement event. To test for the genetic signature of reinforcing selection and identify genes involved in sexual isolation, we adopted a hitchhiking mapping approach targeting genomic regions containing candidate genes for assortative mating in mice. We densely scanned these genomic regions in hybrid zone and allopatric samples using a large number of fast evolving microsatellite loci that allow the detection of recent selection events. We found a handful of loci showing the expected pattern of significant reduction in variability in populations close to the hybrid zone, showing assortative odour preference in mate choice experiments as compared to populations further away and displaying no such preference. These loci lie close to genes that we pinpoint as testable candidates for further investigation.
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Carole M
authors.initials: CM
authors.lastname: Smadja
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Loire
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Caminade
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Marios
authors.initials: M
authors.lastname: Thoma
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Yasmin
authors.initials: Y
authors.lastname: Latour
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Camille
authors.initials: C
authors.lastname: Roux
authors.affiliation: University of Veterinary Medicine Vienna, Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, Vienna, Austria.
authors.forename: Michaela
authors.initials: M
authors.lastname: Thoss
authors.affiliation: University of Veterinary Medicine Vienna, Konrad Lorenz Institute of Ethology, Department of Integrative Biology and Evolution, Vienna, Austria.
authors.forename: Dustin J
authors.initials: DJ
authors.lastname: Penn
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Guila
authors.initials: G
authors.lastname: Ganem
authors.affiliation: Institut des Sciences de l'Evolution UMR 5554 (Centre National de la Recherche Scientifique CNRS, Institut pour la Recherche et le Développement IRD, Université de Montpellier), cc065 Université de Montpellier, Campus Triolet, 34095 Montpellier, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Boursot
mesh_terms: D000818:Animals; D001317:Austria; D003718:Denmark; D005260:Female; D005828:Genetics, Population; D016678:Genome; D023281:Genomics; D006824:Hybridization, Genetic; D008297:Male; D052586:Mating Preference, Animal; D051379:Mice / Q000235:genetics*; D018895:Microsatellite Repeats; D009812:Odorants; D010641:Phenotype; D012641:Selection, Genetic; D017422:Sequence Analysis, DNA
keywords: genomics; hybrid zone; major urinary protein; selective sweep; speciation; vomeronasal receptor