Just heard some disturbing news last night about an increase of Crystinuria in Eng. Mastiffs (and Bullmastiffs).A breeder whom I have a great deal of trust in,told me that it's become a huge problem within the breed(Eng.).I was planning on buying an E.M. pup,but, have decided to hold off until more scientific studies are made.A DNA test exists for Newfoundlands and Labs,but,NOT for other breeds.The markers for this disease aren't found on the same genes in the E.M.,so,a test will have to be developed specifically for them.Newfoundlands are affected by this disease more than any other breed.According to internet info.,ONE dog sired 100 pups which now carry this disease! A genetic test was recently developed to detect PRA in E.M.s(also found on different genes within the breed).This only further demonstrates the need for outcrossing,before it's to late!