No genetic variation detected within isolated relict populations of Saxifraga cernua in the Alps using RAPD markers

Genetic variation in seven relict populations of Saxifraga cernua from three regions of the Alps was investigated using RAPD (random amplified polymorphic DNA) markers. No variation, either within the populations or within the regions, could be demonstrated. Nevertheless, each alpine region was characterized by a unique RAPD phenotype. Absence of genetic variation in these relict populations is attributed to population bottlenecks and founder effects during or following the ice ages. Contrasting hypotheses about the history of these populations, either as survivors of the glacial period or as products of postglacial immigration, are discussed in the light of the data presented.