Progressive retinal atrophy – Rod-cone dysplasia type 3 (PRA-RCD3)
Progressive retinal atrophy (PRA) comprises autosomal recessively inherited diseases that lead to degeneration of retinal photoreceptor cells in dogs and other pets. In general, these diseases are characterized by disturbance of dark vision, visual field defects, and abnormalities in the electroretinogram, which can progress to blindness. The age of onset and rate of retinal degeneration varies between the different forms of the conditions. Some forms of PRA are common to multiple dog breeds, while others are recognized in just a single breed. One form of PRA occurs in Cardigan Welsh Corgis, known as PRA-RCD3.
Rod-cone dysplasias are group of recessively inherited diseases with early onset where photoreceptors are disturbed in their normal development and never manage to develop properly. The progression of rod-cone dystrophy is caused by sequential degeneration of rod and cone photoreceptors.
PRA-RCD3 in the Cardigan Welsh corgi has a similar early onset leading to blindness in the young adult dog and, similar to most forms of canine PRA, is inherited in an autosomal recessive manner.
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