Progressive retinal atrophia (crd2-PRA)
Progressive retinal atrophia (crd2-PRA)
General description
At this PRA form, the cone photoreceptors are degenerated which leads to progressive day blindness and loss of color vision. The rod cells remain predominantly preserved. At the age of 1-2 years, the complete manifestation of the disease occurs.
Breeds
American Pitbull Terrier
Order details
| Test number | 8333 |
| Abbreviation | crd2-PRA |
| Sample material | 0.5 ml EDTA blood, 2x cheek swab, 1x special swab (eNAT) |
| Test duration | 7-14 working days |
Test specifications
| Symptom complex | ophthalmic |
| Inheritance | autosomal recessive |
| Age of onset | 1-2 years |
| Causality | causally |
| Gene | IQCB1 |
| Mutation | INS |
| Literature | OMIA:001675-9615 |
Detailed description
The crd-PRA (Cone-rod dystrophy) is an autosomal recessive inherited photoreceptor disease caused by the predominant loss of cone function. The photoreceptor cells of the retina can be divided into rods or cones depending on their function. The rod cells are specialized for the mesopic vision and contrast sensitivity. The cone cells are responsible for color vision. In contrast to rod-cone dystrophies, where firstly, rod cells are affected and secondly, degeneration of the cone cells results in complete blindness of the dog, cone-rod dystrophies are characterised by the relatively early loss of cone photoreceptors while the rod function remains relatively preserved. The disease usually ends with day blindness. The earliest ophtalmoscopic signs appear at about six month of age. The complete manifestation of the diseases (complete day blindness) occur at an age of around 1 to 2.
