Microsatellite-based genetic diversity and evolutionary relationships of six dog breeds

The Tibetan Mastiff is one of the most archaic, ferocious and the largest dogs in the world. The Kunming dog is the chief working-dog breed in China. In this study, ten microsatellite loci were used to assess the genetic diversity and evolutionary relationships in six dog breeds, including Tibetan Mastiff, Kunming dog, Belgian Malinois, Labrador Retriever, English Springer Spaniel, and German Shepherd. The highest genetic diversity was exhibited by the Tibetan Mastiff, indicating useful protection and little inbreeding in the modern Tibetan Mastiff. Higher genetic diversity was observed in European breeds, supporting the hypotheses that breeders outcross their pure breed dogs occasionally to avoid deleterious effects in Europe. Evolutionary relationships showed that English Springer Spaniel and Labrador Retriever were clustered together, then with the Tibetan Mastiff, consistent with previous cluster results. German Shepherd and Kunming dog were grouped together, coinciding with the breeding history of Kunming dog. It is the first time that Tibetan Mastiff and Kunming dog have been analyzed with microsatellites. (Key Words : Dog, Genetic Diversity, Evolutionary Relationships, Microsatellite)