Test Detail

Late-onset form of progressive retinal atrophy (PRA) of the Golden Retriever, the canine equivalent of human retinitis pigmentosa. It causes photoreceptor degeneration with loss of night vision first and complete blindness afterwards. It is inherited in an autosomal recessive manner and is associated with a frameshift mutation in the SLC4A3 gene, which encodes an anion exchanger expressed in the retina.

Golden Retriever. In the original study (Downs et al. 2011) the variant explained about half of the PRA cases analysed (present in ~56 % of cases and in ~87 % of obligate carriers), with approximate frequencies of 4 % in the United Kingdom, 6 % in Sweden and 2 % in France, and not detected in the United States. Other population frequencies: limited data.

- Test Golden Retriever breeding animals with the SLC4A3 (GR_PRA1) test before breeding
- Do not mate two carriers: 25 % risk of affected homozygotes
- A carrier may be mated to a clear animal; offspring intended for breeding must be tested
- Combine screening with the prcd and GR_PRA2 tests, since PRA is heterogeneous in the breed
- Exclude affected animals from breeding

Differential diagnosis with other forms of Golden Retriever PRA (prcd due to PRCD, GR_PRA2 due to TTC8) and with acquired retinopathies. Electroretinography and ophthalmoscopic examination guide the diagnosis, but confirmation is molecular. A negative result for GR_PRA1 does not rule out PRA caused by other variants, so a complete PRA panel in the breed is advisable.

1. Downs LM et al. 2011, una mutación con cambio de marco en Golden retriever con atrofia progresiva de retina avala SLC4A3 como gen candidato (PMID 21738669)
2. OMIA:001572 PRA GR-PRA1 (SLC4A3)