I am Carla Sanchez and I have been involved with Mastiffs since 1982. I have dedicated my adult life to the preservation and protection of the Mastiff breed. One of my most treasured accomplishments is my work with Dr. Acland from Cornell University that led to the discovery of the gene that causes PRA in Mastiffs. The discovery of this gene not only proved that there were no PRA carriers (a widely accepted notion) but allowed for the development of a simple blood test- now an even simpler cheek swab- that could detect PRA which was more efficient and effective than the CERF exam. I urge all breeders to test for PRA so we can continue to keep this horrible eye disease out of Mastiffs.