.OPTIGEN is a service company established to provide DNA based diagnoses and information about inherited diseases of dogs. For many breeds their researchers have identified the mutations that cause the most common diseases and by working in cooperation with breeders they track these mutations to help reduce the frequency of common diseases in breeding stock.
I have checked with the Optigen website to see if there are any genetic DNA tests available at this time for the Miniature Schnauzer and unfortunately there are not. (I keep hoping researchers will discover it!) So I asked my veterinary what kind of screening is currently available for Miniature Schnauzer breeders and she recommended screening for PRA.