Official Kennel Club DNA Testing Scheme
Progressive Retinal Atrophy (prcd-PRA)
PRA is a disease that causes the retina of the eye to degenerate slowly over time, the result is declining vision and eventual blindness. Progressive rod-cone degeneration (prcd) is just one type of PRA, it occurs as a result of degeneration of the rod and cone photoreceptor cells of the Retina. Most affected dogs will show no signs of vision loss until around 3 to 5 years of age or later. The rod type cells are affected first and affected dogs will initially have vision deficits in dim light (night blindness) and loss of peripheral vision. Over time affected dogs continue to lose night vision and begin to show visual deficits in bright light. This type of PRA was originally discoverd in black Giant Schnauzers in America. The causal mutation was found to be the same as a few other breeds, for which a DNA test already existed via Optigen. Since then carriers of prcd-PRA are known to have been imported into the UK. According to the Orthopaedic Foundation For Animals, their statistics show a 7.1% carrier rate for prcd-PRA in the Giant Schnauzer.
The mode of inheritance is autosomal recessive, which means a dog will only be affected if they have 2 copies of the recessive gene, one from the sire and one from the dam. The result of the DNA test will be either clear, carrier or affected. See Breeding from a DNA Tested Dog for further information regarding the result and breeding advice.
A DNA test for prcd-PRA is available via:
This DNA test can be completed by simple cheek swabs posted back to the appropriate lab, see the test providers websites for more information.