This is the genetics report from UC Davis Veterinary School stating Sultan is negative for PKD1. The genetic test for PKD1 is only good for Persians and cats who are bred to Persian cats. Even Persian cats have to be sonographed for PKD in order to be negative. There are many more mutations of the PKD gene that have not been identified yet. Even when they have been it will still be more efficient and accurate to have testing conducts by a Board Certified Veterinary Internist and sonograph than by genetic sample.