Progressive retinal atrophy (PRA) is a category of different progressive conditions leading to retinal atrophy and potential blindness. Three separate mutations (PRA-PRCD, GR-PRA1 and GR-PRA2) have been identified to date that can lead to PRA in Golden Retrievers. Golden Retriever Progressive Retinal Atrophy 2 (GR-PRA2) is a late-onset inherited eye disease that typically shows clinical symptoms including retinal degeneration at approximately 5 years of age with variation in the age of onset. Primary clinical signs of the disease include changes in reflectivity and appearance of a structure behind the retina that can be diagnosed through a veterinary eye exam. Disease progression can include thinning of the retinal blood vessels leading to decreased blood flow to the retina. Dogs affected by GR-PRA2 initially have loss of vision in dim light (also known as night blindness) followed by loss of peripheral vision with eventual progression to complete blindness in most affected dogs.

• Golden Retriever

A (CLEAR/NORMAL): These dogs have two copies of the normal gene and will neither develop PRA due to the GR-PRA2 mutation nor pass this mutation to their offspring.

B (CARRIER/NOT AFFECTED): These dogs have one copy of the normal gene and one copy of the mutation associated with this disease. They will not develop PRA due to the GR-PRA2 mutation but will, if bred, pass the mutation to 50% of its offspring, on average.

C (AT RISK/AFFECTED): These dogs have two copies of the mutation associated with this disease which will likely result in loss of vision in dim light with eventual progression to complete blindness.