Retinitis pigmentosa type 28 (RP28) is one of several types of retinitis pigmentosa, a group of inherited disorders causing gradual vision loss.
The problem lies in the cells that sense light in the eyes. The first sign is often trouble seeing in the dark, and it can progress to losing side vision, creating “tunnel vision,” and eventually, central vision may also be lost. RP28 usually starts causing visual difficulties in a person’s 20s or 30s, and the decline in vision is slower compared to other types of retinitis pigmentosa. Severe visual handicap typically happens in a person’s 50s, and legal blindness occurs by their 60s or 70s. RP28 only affects the eyes, and there are no other symptoms in the rest of the body. Currently, there’s no cure for retinitis pigmentosa, but using sunglasses that block UV-A and UV-B rays is recommended, and certain optical aids can make eyes more comfortable. Some individuals might slow down the degeneration of the retina with vitamin A palmitate therapy. Counseling and lifestyle adjustments can also help individuals manage the progressive loss of vision.
RP28 is caused by pathogenic (disease-causing) variants in the FAM161A gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background. For example, individuals of Ashkenazi Jewish descent have a 1 in 214 chance to be a carrier.
Other names for this condition are pigmentary retinopathy, rod-cone dystrophy, and tapetoretinal degeneration.