A form of progressive retinal atrophy of the Puli caused by a mutation in the BBS4 gene, linked to Bardet-Biedl syndrome. It produces progressive degeneration of photoreceptors and gradual vision loss. It is incurable and progresses to blindness without causing pain.

Specific to the Puli. Limited data on carrier frequencies; the breed is small and the disease is considered rare.

- Initial loss of night vision
- Tapetal changes in the ocular fundus
- Pupillary dilation
- Progressive decrease in daytime vision
- Blindness in advanced stages
- Possible additional features of BBS syndrome

PRA in the Puli was investigated as a distinct entity and was associated with a mutation in the BBS4 gene, one of the Bardet-Biedl syndrome genes. In 2017, Chew and colleagues identified a nonsense variant in BBS4 (c.58A>T, p.Lys20*) that segregates with PRA in the Hungarian Puli. The finding reinforced the role of primary cilia genes in canine PRAs. The genetic test allows carrier control in the breed.

- Test breeding dogs before mating
- Do not cross two carriers
- A carrier may be crossed with a clear individual; test the offspring intended for breeding
- Preserve genetic diversity given the small breed population

As in other BBS-PRAs, it is advisable to rule out additional features of the syndrome (polydactyly, renal anomalies). Differential diagnosis with other PRAs. There is no curative treatment.

1. Chew T et al. 2017, A Coding Variant in the Gene Bardet-Biedl Syndrome 4 (BBS4) Is Associated with a Novel Form of Canine Progressive Retinal Atrophy. G3 (Bethesda) 7(7):2327-2335. PMID: 28533336. OMIA:002045-9615.