Affected genes: SAG
Inheritance: Autosomal Recessive
Mutation:  CanFam3.1 25 g.44843440T>C c.1216T>C
OMIA link: 001876-9615

Appropriate breeds for testing: Basenji

Symptoms:
PRA (progressive retinal atrophy) is characterized by degeneration of the photoreceptors leading to progressive loss of vision, and eventually blindness.
In the Basenji, PRA is observed in adulthood, with initial loss of vision in dim light (night blindness) and reduction of the visual field (tunnel vision), gradually progressing to total blindness. Many Basenjis with PRA retain adequate daytime vision for many years, and sometimes for the rest of their lives. This phenotype is very similar to PRA-PRCD, a late-onset retinal degeneration affecting several breeds.

References:
Goldstein O, Jordan JA, Aguirre GD, Acland GM. A non-stop S-antigen gene mutation is associated with late onset hereditary retinal degeneration in dogs. Mol Vis. 2013 Aug 27;19:1871-84. PMID: 24019744; PMCID: PMC3762564.