Retina Dysplasia and/or Optic Nerve Hypoplasia

Affected dogs may have visual impairment which may be observed as being reluctant to go down the stairs, bumping into door frames or corners, taking a longer time to fetch a toy, or displaying behavior concerns. Affected dogs may have abnormalities in one or both eyes including persistent pupillary membranes (PPM), retinal and optic nerve malformations, cataracts, deformed lens, and abnormal eye movement (congenital nystagmus).

Severe ocular abnormalities may be observed at birth. In milder cases, changes may be observed on ophthalmologic examination at between one to 12 months of age.

Affected dogs may have changes observed on a basic eye examination or a more comprehensive exam performed after dilating the pupils. The definitive diagnosis of retinal dysfunction is by electroretinography (ERG), which records the electrical potentials of the retina in response to a light stimulus. Referral to a veterinary ophthalmologist may be needed for a definitive diagnosis.

Currently, there is no treatment for this condition.

Talk to your vet about your dog’s retina dysplasia and optic nerve hypoplasia result so you can discuss whether any signs are present, plan ongoing monitoring, and make adjustments at home to keep them comfortable and confident.

The severity of this condition can vary. Some dogs adjust well with partial vision, while others may have more significant vision loss.

Help your dog navigate safely by keeping furniture in consistent locations, using verbal cues, and keeping them on a leash in unfamiliar areas.

Please note, several forms of Progressive Retinal Atrophy (PRA) have been identified in Golden Retrievers. Please consult with your veterinarian should you have any concerns about your dog’s eyes or eyesight, even if your dog tested clear for this variant.

Penetrance: This variant is thought to have an autosomal dominant inheritance with incomplete penetrance, which in this instance means that although only one copy of the variant is needed to cause the disorder, not all dogs with one copy will develop retinal or optic nerve abnormalities.

Gene

SIX6 Exon 1

Inheritance type

Dominant

Clinical category

Ophthalmologic

Citations

1. Hug et al 2019

• Golden Retriever