Development of noninvasive genetic identification methods and polymorphic microsatellites for the Pyrenean desman (Galemys pyrenaicus)

The Pyrenean desman (Galemys pyrenaicus) is probably one of the most threatened European mammal species. This small insectivorous and semi-aquatic species is endemic to the Pyrenean Mountains and of the north of the Iberic Peninsula. Many biologic aspects of this species are currently suffering from a major lack of information, particularly those concerning its genetics. Therefore the implementation of conservative efforts for the Pyrenean Desman remains extremely difficult. In order to improve the knowledge of this vulnerable species and notably, to better understand its distribution area, the first aim of our research was to develop non invasive genetic identification methods based on faeces. The second aim was the development of several polymorphic microsatellites markers in order to have a first look at the genetic structure of the Pyrenean Desman in its French distribution area. The identification methods were developed on the basis of the sequencing of a small mitochondrial DNA (cyt b) fragment as well as a RFLP method. These approaches led to the identification of the Pyrenean desman and to the differentiation of the latter from two other species living in the same type of habitat, the white-throated dipper (Cinclus cinclus) and the water shrew (Neomys fodiens). More than fifteen polymorphic microsatellites markers could be found for the Pyrenean Desman and their genotyping revealed a low number of alleles per locus (two to five). The results of this preliminary work tend to show a low genetic diversity for the Pyrenean Desman but this result needs to be confirmed in the future with a more extended and complete study