Liver Shunts are not always genetic. They can be acquired also. I have a shunt- survivor that had the surgery. Her's did happen to be inherited. If it is a repairable shunt, and you elect to have the surgery done, your dog can live a long happy life after recouperating. Unfortunately, the surgery is very costly, and a lot of people can not afford to have it done, but there are places that will help. Terri Shumsky Liver shunt foundation is one that helps. You can read about shunts here, and how we found it in my dog.
http://www.yorkieviews.com/livershunt.htm