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Canine Mendelian disease record

Dominant Progressive Retinal Atrophy (DPRA)

Dominant Progressive Retinal Atrophy (DPRA). Autosomal dominant. Observed in 1 of 266 breeds tested in the Sniff Atlas, with measured at-risk genotype frequencies drawn from 242,661 dogs (Donner 2023). Because this is a dominant trait, a single copy places a dog at risk rather than making it a silent carrier; whether the phenotype appears still depends on penetrance, modifier genes, and environment.

Dominant trait. A single copy of this variant places a dog at risk; it does not make the dog a silent carrier. The breed frequencies below are therefore at-risk frequencies, and penetrance plus modifier genes determine whether the phenotype actually appears.

OMIA identifier
OMIA:001346-9615
Autosomal dominant
Source dataset
Sniff Atlas v1.0.1 / DOI
The human connection

A model of human congenital stationary night blindness autosomal dominant 1

This is the canine counterpart of congenital stationary night blindness autosomal dominant 1 in people. That makes affected dogs a naturally-occurring model of the human disease, and it is part of why studying dogs moves medicine forward for everyone. It does not mean your dog has the human disease. It means the two share an underlying biology.

In people, the disease is described as: Any congenital stationary night blindness in which the cause of the disease is a mutation in the RHO gene.

In humans it is also called: CSNBAD1, RHO congenital stationary night blindness.

MONDO:0012498 OMIM 136880OMIM 610445

Mapped from OMIA via the human disease's OMIM entry to the Mondo Disease Ontology (Monarch Initiative, CC-BY 4.0). Closely related human conditions exist for this gene. Sniff renders this as a model-of link; the canine disease remains the subject of this page.

About this disease

From OMIA's curated record

Documented in OMIA (Online Mendelian Inheritance in Animals). This describes the disease as recorded in the published literature, not a prediction for any individual dog. As of 2026-06-03.

Summary

This disorder has been renamed in OMIA on the basis of the review by Miyadera et al. (2011) (PMID:22065099)

Clinical features

As detailed by Kijas et al. (2002), rod vision is normal for at least the first few months. But by 12-18 months, degeneration is evident, spreading slowly from a disease focus in one retinal region. In addition, there is an abnormally slow recovery of rod photoreceptor function after exposure to light.Homozygotes have more severe clinical signs than heterozygotes [Frank Nicholas, 26 June 2002] Iwabe et al. (2016) reported that "a short single exposure to a dose of white light that is not retinotoxic in [wild-type] WT dogs causes in the T4R RHO retina an acute loss of ONL in the central to mid peripheral region that keeps progressing over the course of several weeks. However, this severe retinal damage does not affect visual behavior presumably because of islands of surviving photoreceptors found in the area centralis including the newly discovered canine fovea-like area, and the lack of damage to peripheral photoreceptors."

Molecular genetics

Kijas et al. (2002) discovered an autosomal-dominant progressive retinal atrophy in English Mastiff dogs, with clinical signs very similar to a human dominant retinitis pigmentosa that is due to mutations in the gene for rhodopsin. Taking the rhodopsin gene as a strong comparative candidate, Kijas et al. (2002) sequenced all five exons of the canine rhodopsin gene from a heterozygous affected dog, and discovered a missense mutation (C-to-G transversion) at nucleotide 11, giving rise to a Thr-to-Arg amino acid substitution at position 4 of the peptide (T4R), in the extracellular domain. Noting that the mutation generates a BsmFI restriction fragment length polymorphism, Kijas et al. genotyped 26 affected and 21 related normal English Mastiffs. Three of the affected dogs were homozygous for the mutant allele; the rest were heterozygous. All related normal dogs were homozygous for the normal allele, as were 156 normal dogs from 17 other dog breeds [Frank Nicholas, 26 June 2002] Kijas et al. (2003) noted that "Testing of PRA-affected animals from [other] 16 breeds revealed that none carry the T4R mutation, indicating a different cause of PRA".

Human analog

OMIA links this condition to its human counterpart in OMIM (Mendelian Inheritance in Man), the place to read across to the deeper human literature for the same biology.

Disease · OMIM 136880 Disease · OMIM 610445 Disease · OMIM 613731 Gene · OMIM 180380

Source: OMIA (Nicholas, Tammen & the Sydney Informatics Hub), entry OMIA:001346-9615, doi:10.25910/2AMR-PV70 (CC-BY 4.0).

The evidence

Published references

The peer-reviewed papers behind this disease, curated by OMIA. Starred entries are OMIA-designated landmark papers. Showing 6 of 19.

References curated by OMIA (Nicholas, Tammen & the Sydney Informatics Hub), doi:10.25910/2AMR-PV70 (CC-BY 4.0). Full list at the OMIA entry.

Predict a litter

Set each parent's status for Dominant Progressive Retinal Atrophy (DPRA) and see the odds for their puppies. Single dominant variant, exact Mendelian math.

Parent A
Parent B
NDAffected
NDAffected
NNUnaffected
NNUnaffected
Unaffected50%
Affected50%

These are the genetic odds for one known variant, not a promise: a real litter varies around them, and penetrance or other genes can change whether the condition ever appears. Use it to avoid pairing two carriers and to keep a line healthy, not to engineer a dog. Inheritance mode per OMIA.
Your breed

See what Dominant Progressive Retinal Atrophy (DPRA) looks like in your dog's breed.
At-risk frequency by breed

Top 1 well-sampled breeds (n ≥ 50)

Maximum at-risk frequency per breed across variants in the Donner 2023 cohort, with . The list below is split into well-sampled breeds (n ≥ 50 tested) and small-sample breeds (n < 50, where the Wilson CI typically spans more than 20 percentage points and frequencies should not be compared directly to the well-sampled entries). Frequencies are population-level, not per-litter or per-line.

0%1%2%
Mastiff0.46% · n 767
n = 767 dogs · Donner et al. 2023 carrier-screening cohort · Sniff Atlas
Each bar is one well-sampled breed; the whisker is its Wilson 95% CI, and fainter bars have wider intervals. Frequencies are population-level, not per-litter. Carrier status for Dominant Progressive Retinal Atrophy (DPRA) is measured; phenotype outcome depends on penetrance and modifiers.
▸ Full table with Wilson 95% confidence intervals
Breed At-risk frequency n tested
Mastiff 0.46% 767

265 additional breeds in the Donner 2023 cohort were tested but showed no at-risk genotypes.

Penetrance

From genotype to phenotype

For this dominant trait, a dog with even one copy is at risk, not a silent carrier. Penetrance is the fraction of at-risk dogs that actually develop the phenotype. The Donner 2023 S4 table tracks this for 1 variant(s) underlying this disease in the cohort.

At-risk dogs evaluated
2
Phenotype confirmed
0
Penetrance range
not yet quantifiable

Fewer than 20 at-risk dogs evaluated; too few to state a penetrance figure.

Predicted disease relevance at the per-dog level is UNPROVEN. The at-risk frequency is measured; phenotype outcome is governed by penetrance, environment, and modifier loci. Consult a veterinarian for clinical interpretation.

How to cite this record

Citations

If you use this record in published work, cite the Sniff Atlas (the published dataset that carries the breed-level carrier frequencies) and the upstream sources:

  • Sniff Atlas v1.0.1 for the per-breed carrier frequencies:

    Gehring, M. (2026). Sniff Atlas v1.0.1. Zenodo. https://doi.org/10.5281/zenodo.20566358. CC-BY 4.0.

  • OMIA for the disease definition, inheritance, and gene assignment:

    Nicholas, F. W., & Tammen, I. (2024). OMIA. Sydney Informatics Hub, The University of Sydney. https://doi.org/10.25910/2AMR-PV70. Entry: OMIA:001346-9615.

  • Donner et al. 2023 for the breed × variant carrier-frequency cohort:

    Donner, J., Freyer, J., Davison, S., Anderson, H., Blades, M., Honkanen, L., et al. (2023). Genetic prevalence and clinical relevance of canine Mendelian disease variants in over one million dogs. PLOS Genetics, 19(2), e1010651. https://doi.org/10.1371/journal.pgen.1010651.

Full citation formats (BibTeX, RIS, CITATION.cff) at sniff.world/cite.

Related

Related

Last updated
Sources: Sniff Atlas v1.0.1 · OMIA OMIA:001346-9615 · Donner et al. 2023