Retinitis Pigmentosa (RP)
An inherited disease caused by gene defects instructing the cells in the retina to miss fire. There are a number of hereditary routes to RP, either male only with females as carriers (X linked) familial inheritance where both male and female siblings have a 50% chance of suffering RP from one of their parents and recessive inheritance where two carriers create a 25% chance of a sibling with RP whilst there appears to be no familial link.
There is no cure for RP although many find its onset (between 10 and 30 years old) to be very slow.
The malfunction can start with central vision but in many cases vision is loss from the outside in creating the effect of tunnel vision.
Early symptoms are of poor vision in dimly lit areas and in its later stage glare from light sources can occur. It can be linked to a number of other disabilities which are normally denoted as syndromes. Ushers syndrome for example demonstrates hearing impairment as well as RP.
RP sufferers are more prone to cataracts.