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Juvenile-onset inherited retinopathy of the Labrador Retriever phenotypically close to human Stargardt disease: progressive cone-rod degeneration that begins in the central area (fovea equivalent) and later extends to the visual streak and the peripheral retina, with slow visual deterioration. It is caused by a loss-of-function mutation in the ABCA4 gene, involved in retinoid transport in photoreceptors.

Described in the Labrador Retriever. In a Japanese population of 120 Labradors, a mutant allele frequency of 0.246 was found (42.5% heterozygotes and 3.3% homozygotes; Takanosu, 2026), indicating a relatively high frequency in the breed. Not to be confused with prcd-PRA.

- If the genetic test is available, test breeding animals for ABCA4
- Do not mate two carriers: 25% affected homozygotes
- A carrier may be mated to a clear animal; test offspring intended for breeding
- Exclude affected animals from breeding
- Complement with periodic ophthalmological examination and, if appropriate, electroretinography

The differential diagnosis includes prcd-PRA, GTPBP2-related PRA and other retinopathies of the Labrador. Electroretinography characterises the cone-rod pattern. There is no curative treatment. The dog is a natural model of human ABCA4-related Stargardt disease; ELOVL4 is a gene of the human STGD3 form, but it has not been described in the dog.

1. Mäkeläinen S, et al. An ABCA4 loss-of-function mutation causes a canine form of Stargardt disease. PLoS Genet. 2019;15(3):e1007873. PMID: 30889179
2. Ekesten B, et al. Abnormal appearance of the area centralis in Labrador retrievers with an ABCA4 loss-of-function mutation. Transl Vis Sci Technol. 2022;11(2):36. PMID: 35201338
3. Takanosu M, et al. Genotype frequency of Stargardt disease in Labrador retrievers in Japan. J Vet Med Sci. 2026;88(8):1158-1160. PMID: 42203465
4. OMIA:002179-9615. Stargardt disease 1 in Canis lupus familiaris. https://omia.org/OMIA002179/9615/