Retinal atrophy, progressive (Late-onset blindness, PRA-rdAc)

 

Gene: CEP290

Transmission: Autosomal recessive

For an autosomal recessive genetic disease, an animal must have two copies of the mutation in question to be at risk of developing the disease.  Both parents of an affected animal must be carriers of at least one copy of the mutation.  Animals that have only one copy of the mutation are not at risk of developing the disease, but are carrier animals that can pass the mutation on to future generations.

Mutation: Substitution, CEP290 gene; T>A, intron50-51

Medical system: Ocular

Breeds: Abyssinian, American Shorthair, Balinese, Cornish Rex, Devon Rex, Domestic Cat, Donskoy, European Shorthair, Highland Lynx, Maine Coon, Manx, Oriental Shorthair, Peterbald, Pixie-bob, Ragdoll, Savannah, Scottish Fold, Siamese, Somali, Sphynx, Tennessee Rex

Age of onset of symptoms: between 1 and 2 years of age

PRA-rdAc (late onset blindness) is a recessive genetic disease of the retina.  Although this disease has been diagnosed in a number of cat breeds, it is particularly associated with Abyssinians.  This disease belongs to a family of eye diseases characterized by progressive retinal atrophy (PRA).  The photoreceptors of the retina develop normally, but then begin to degenerate.  The rod photoreceptors, responsible for night vision as well as peripheral vision, begin to degenerate between 1 and 2 years of age, resulting in night blindness.  This can change the behavior of the affected animal, which can become disorientated and hesitant in conditions of low light.  This is followed by degeneration of the cone photoreceptors, responsible for color and day vision, eventually resulting in complete blindness by the age of 3 to 5 years.  There is no treatment for this disease, although affected animals can adapt to the condition.

 

References:

OMIA link: [1244-9685]

Minella AL, Narfström Wiechel K, Petersen-Jones SM. (2023) Alternative splicing in CEP290 mutant cats results in a milder phenotype than LCA CEP290 patients. Vet Ophthalmol 26(1):4-11. [pubmed/36495011]

Anderson H, Davison S, Lytle KM, et al. (2022) Genetic epidemiology of blood type, disease and trait variants, and genome-wide genetic diversity in over 11,000 domestic cats.  PLoS Genet. 16;18(6):e1009804.  [pubmed/35709088]

May CA, Narfström K. (2012) Retinal capillary morphology in the Abyssinian cat with hereditary retinal degeneration. Exp Eye Res 99:45-7.  [pubmed/22525835]

Menotti-Raymond M, David VA, Pflueger S, et al. (2010) Widespread retinal degenerative disease mutation (rdAc) discovered among a large number of popular cat breeds. Vet J. 186(1):32-38. [pubmed/19747862]

Menotti-Raymond M, David VA, Schaffer AA, et al. (2007) Mutation in CEP290 discovered for cat model of human retinal degeneration. Journal of Heredity 98(3):211-220. [pubmed/17507457]