title: Genetic differentiation within and away from the chromosomal rearrangements characterising hybridising chromosomal races of the western house mouse (Mus musculus domesticus).
abstract: The importance of chromosomal rearrangements for speciation can be inferred from studies of genetic exchange between hybridising chromosomal races within species. Reduced fertility or recombination suppression in karyotypic hybrids has the potential to maintain or promote genetic differentiation in genomic regions near rearrangement breakpoints. We studied genetic exchange between two hybridising groups of chromosomal races of house mouse in Upper Valtellina (Lombardy, Italy), using microsatellites. These groups differ by Robertsonian fusions and/or whole-arm reciprocal translocations such that F1 hybrids have a chain-of-five meiotic configuration. Previous studies showed genetic differentiation in two chromosomes in the chain-of-five (10 and 12) close to their centromeres (i.e. the rearrangement breakpoints); we have shown here that the centromeric regions of the other two chromosomes in the chain (2 and 8) are similarly differentiated. The internal chromosomes of the chain (8 and 12) show the greatest differentiation, which may reflect pairing and recombination properties of internal and external elements in a meiotic chain. Importantly, we found that centromeric regions of some non-rearranged chromosomes also showed genetic differentiation between the hybridising groups, indicating a complex interplay between chromosomal rearrangements and other parts of the genome in maintaining or promoting differentiation and potentially driving speciation between chromosomal races.
authors.affiliation: Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK.|Department of Evolutionary Genetics, Leibniz-Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str.17, 10315, Berlin, Germany.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Förster
authors.affiliation: Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK.|Fera Science, Sand Hutton, York, YO41 1LZ, UK.
authors.forename: Eleanor P
authors.initials: EP
authors.lastname: Jones
authors.affiliation: Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK.|Department of Ecology and Genetics, Uppsala University, Norbyv 18 D, 752 36, Uppsala, Sweden.|Department of Ecology and Evolution, Corson Hall, Cornell University, Ithaca, NY, 14853-2701, USA.
authors.forename: Fríða
authors.initials: F
authors.lastname: Jóhannesdóttir
authors.affiliation: Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK.|CESAM - Centre for Environmental and Marine Studies, Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, 1749-016, Lisbon, Portugal.
authors.forename: Sofia I
authors.initials: SI
authors.lastname: Gabriel
authors.affiliation: Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK.|Instituto de Biología Subtropical, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones, Félix de Azara 1552, N3300LQH, Posadas, Misiones, Argentina.
authors.forename: Mabel D
authors.initials: MD
authors.lastname: Giménez
authors.affiliation: Institute of Marine Science, Burapha University, Chonburi, Thailand.
authors.forename: Thadsin
authors.initials: T
authors.lastname: Panithanarak
authors.affiliation: Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK.|Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 S, Michele all'Adige, TN, Italy.
authors.forename: Heidi C
authors.initials: HC
authors.lastname: Hauffe
authors.affiliation: Department of Biology, University of York, Wentworth Way, York, YO10 5DD, UK. jeremy.searle@cornell.edu.|Department of Ecology and Evolution, Corson Hall, Cornell University, Ithaca, NY, 14853-2701, USA. jeremy.searle@cornell.edu.
authors.forename: Jeremy B
authors.initials: JB
authors.lastname: Searle
mesh_terms: D000818:Animals; D002875:Chromosomes / Q000235:genetics; D049810:Genetic Speciation; D014644:Genetic Variation; D005828:Genetics, Population; D006824:Hybridization, Genetic / Q000235:genetics*; D059785:Karyotype; D051379:Mice; D018895:Microsatellite Repeats / Q000235:genetics*; D008957:Models, Genetic; D011995:Recombination, Genetic / Q000235:genetics*
keywords: Robertsonian fusion; chromosomal hybrid zone; introgression; microsatellites; speciation