Some St Bernards have very short snouts while others have long snouts. There are a few reasons for this difference. One reason is that some dogs have a gene that makes their snout shorter. This gene is passed down from the dog's parents and can be found in about 25% of all Saint Bernards. If you want to get a dog with a short snout, you'll need to look for one that has this gene. Another reason why some St Bernards have short Snouts while others have long Snouts is because of how they are bred. When a breeder wants to produce a long-snouted Saint Bernard, they will crossbreed two short-nosed dogs. This results in puppies with both the genes for a long and short snout.