Disease overview

Rod-Cone Dysplasia 2 (RCD2) is a form of early-onset, progressive retinal atrophy. This is a non-painful eye disorder that affects both types of photoreceptors: rods and cones. Rod cells are responsible for vision in low light conditions and for detecting and following movement, while cone cells detect color and adjust brightness, but do not work as well in low light. RCD2 causes retinal degeneration and can lead to complete blindness by 6-8 months of age.

Gene name

RD3

Inheritance

Autosomal recessive

Signs and symptoms

Changes in behavior indicative of vision loss include reluctance to go down stairs or into a dark room, and bumping into door frames or furniture. There may be an increased reflectivity to the eye. This disease first presents with symptoms of night blindness as early as 6 weeks of age and typically leads to complete blindness by 6 to 8 months of age.

How is it diagnosed

Thorough examination of the eyes and clinical signs. A veterinary ophthalmologic exam can determine if there are changes in the eye that have or will lead to vision loss. Genetic testing is necessary to determine if there is an underlying genetic cause, which can assist veterinarians with diagnosis and help breeders identify affected and carrier dogs.

Breeds at higher risk

Citations

Kukekova AV, Goldstein O, Johnson JL, Richardson MA, Pearce-Kelling SE, Swaroop A, Friedman JS, Aguirre GD, Acland GM. Canine RD3 mutation establishes rod-cone dysplasia type 2 (rcd2) as ortholog of human and murine rd3. Mamm Genome. 2009 Feb;20(2):109-23. doi: 10.1007/s00335-008-9163-4. Epub 2009 Jan 9. PMID: 19130129; PMCID: PMC2652121.

Disclaimer

Disease diagnosis and treatment should always be performed by a veterinarian. The following information is for educational purposes only.