Test Detail
rcd1-PRA (Irish Setter and Irish Red and White Setter)
Ocular · Dog
Progressive retinal atrophy due to rod-cone dystrophy type 1 (rcd1) in the Irish Setter and the Irish Red and White Setter. Early and progressive degeneration of retinal photoreceptors leading to blindness. It was one of the first forms of canine PRA characterised at the molecular level.
Incidence
It affects the Irish Setter and the Irish Red and White Setter. rcd1 is one of the classic PRAs; the genetic test has made it possible to reduce the frequency of carriers in breeding programmes, although current prevalence figures are not published systematically (limited data).
Breeder management
- Genotype breeding animals before mating\n- Do not cross carrierĂ—carrier (25 % risk of affected homozygotes); carrierĂ—clear produces 0 % affected and 50 % carriers\n- An affected animal must not be bred; a carrier can be crossed with a clear animal without producing affected offspring\n- Annual ophthalmological examination (ECVO) as a complement
Specialist notes
The differential diagnosis includes other Setter PRAs, in particular rcd4 (associated with a frameshift in C2orf71), with a later onset than rcd1. Definitive confirmation requires the PDE6B genetic test.
References
1. Suber et al. (1993). Irish setter dogs affected with rod/cone dysplasia contain a nonsense mutation in the rod cGMP phosphodiesterase beta-subunit gene. Proc Natl Acad Sci U S A 90:3968-3972. PMID: 8387203
2. Clements et al. (1993). Confirmation of the rod cGMP phosphodiesterase beta subunit (PDE beta) nonsense mutation in affected rcd-1 Irish setters in the UK and development of a diagnostic test. Curr Eye Res 12:861-866. PMID: 8261797
3. Aguirre et al. (1999). Frequency of the codon 807 mutation in the cGMP phosphodiesterase beta-subunit gene in Irish setters and other dog breeds with hereditary retinal degeneration. J Hered 90:143-147. PMID: 9987922
4. Downs et al. (2013). Late-onset progressive retinal atrophy in the Gordon and Irish Setter breeds is associated with a frameshift mutation in C2orf71. Anim Genet 44:169-177. PMID: 22686255
5. OMIA:000882-9615. Retinal atrophy - Rod-cone dysplasia 1 in Canis lupus familiaris (dog).
2. Clements et al. (1993). Confirmation of the rod cGMP phosphodiesterase beta subunit (PDE beta) nonsense mutation in affected rcd-1 Irish setters in the UK and development of a diagnostic test. Curr Eye Res 12:861-866. PMID: 8261797
3. Aguirre et al. (1999). Frequency of the codon 807 mutation in the cGMP phosphodiesterase beta-subunit gene in Irish setters and other dog breeds with hereditary retinal degeneration. J Hered 90:143-147. PMID: 9987922
4. Downs et al. (2013). Late-onset progressive retinal atrophy in the Gordon and Irish Setter breeds is associated with a frameshift mutation in C2orf71. Anim Genet 44:169-177. PMID: 22686255
5. OMIA:000882-9615. Retinal atrophy - Rod-cone dysplasia 1 in Canis lupus familiaris (dog).