There is a very informative on-line site called the Berner-Garde Foundation which collects health and pedigree information about the Bernese Mountain Dog. It is an open site, which means that anyone can get access to the information. Breeders and dog owners use this site to share information about their dogs in order to try help improve the health of the breed.
Both of my dogs came to me with a 4 generation pedigree and that is the pedigree that you see when you look up their information in the Berner-Garde database. Tonight, I was looking at their pedigrees a bit further back using the Berner-Garde database, and what did I find? Maggie and Bosley have a common ancestor. Jerry V Rosiendlithal is a dog from Switzerland that shows up 5 generations back in Maggie's pedigree and 6 generations back in Bosley's pedigree. I never expected to find a link in Maggie and Bosley's pedigrees, but I should not be too surprised, as Bernese have a very limited gene pool and Jerry V Rosiendlithal shows up over and over in many pedigrees. Jerry is an FCI International/World/Swiss/Nordic/Danish Champion. No wonder he was so popular.