Clear
Genotype: N / N [ Homozygous normal ]
The dog is noncarrier of the mutant gene.
It is very unlikely that the dog will develop Progressive Retinal Atrophy (generalized PRA). The dog will never pass the mutation to its offspring, and therefore it can be bred to any other dog.
Carrier
Genotype: N / G-PRA [ Heterozygous ]
The dog carries one copy of the mutant gene and one
copy of the normal gene.
It is very unlikely that the dog will develop Progressive Retinal Atrophy (generalized PRA) but since it carries the mutant gene, it can pass it on to its offspring with the probability of 50%. Carriers should only be bred to clear dogs.
Avoid breeding carrier to carrier because 25% of their offspring is expected to be affected (see table above)
Affected
Genotype: G-PRA / G-PRA [ Homozygous mutant ]
The dog carries two copies of the mutant gene and
therefore it will pass the mutant gene to its entire offspring.
The dog is likely to develop Progressive Retinal Atrophy (generalized PRA) and will pass the mutant gene to its entire offspring
