What are Hereditary Retinal Degenerations?
Hereditary retinal disorders (HRDs) are a heterogenous group of mostly rare ocular diseases for which no effective cure is currently available. Characteristics are impaired light sensing and / or signal transmission within the neuroretina that ultimately lead to a decrease of visual acuity, increase of detection threshold, constrictions or defects of the visual field and / or colour vision defects. The pathology affects the photoreceptors, the retinal pigment epithelium and / or the processing and transmitting of first order neurons.
With an estimated prevalence of 1:2.500 and approximately 30.000 to 40.000 affected patients in Germany, HRDs represent a clinically important group of diseases. They are the major cause of disability and legal blindness in the working population and cause a dramatic loss of life quality of affected patients.
The most common form of HRDs is the so called retinitis pigmentosa (RP) Retinitis Pigmentosa (RP).
The first symptom usually is night blindness, followed by the progressive loss in the peripheral visual field in daylight, known as tunnel vision. To date 47 distinct causative genes are known for RP. For a simulation of vision with RP, visit the webpage of the German patient organisation PRO RETINA e. V
Amongst many others, HRDs comprise also
- Leber Congenital Amaurosis (15 known genes)
- Stargardt disease
- Bardet Biedl syndrome (to date 13 causative genes are known)
- Cone or rod-cone dysthrophies (22 known genes) and the
- Usher-syndrom (9 causative genes)
Common to all disorders is the ability of the clinicians to diagnose the diseases – they are, however, not able to offer patients affected by HRDs any treatment or therapy