• Open Access

Study of Gene Flow Through a Hybrid Zone in the Common Shrew (Sorex Araneus) Using Microsatellites


Nicolas Lugon Moulin, Institute of Zoology and Animal Ecology, Biology Building, University of Lausanne, 1015 Lausanne-Dorigny, Switzerland


The common shrew (Sorex araneus) is subdivided into several chromosomal races. As hybrid zones between them have been characterized, this organism is of particular interest in studying the role of chromosomes in speciation. Six microsatellite loci were used to evaluate the level of gene flow in the S. araneus hybrid zone between the Cordon and Valais races. Most of these loci were very polymorphic, the total number of alleles detected per locus ranging from 3 to 20. Using Mantel tests, we showed that the effect of rivers as barriers to gene flow is less important at this sampling scale. The effect of the chromosomal race is of particular importantance in diminishing gene flow.