Retinitis Pigmentosa

Retinitis Pigmentosa is a disease that may consist of a wide variety of mutations in the genes that codes for proteins associated with the retina. These mutations disrupt the visual systems and often lead into blindness. The retinal cells die as a result of the mutations due to the symptoms of Retinitis Pigmentosa. Scientists are trying to bring back vision of Retinitis Pigmentosa patients though gene supplementation, implantation of photoreceptors, or implantation of electronic implants, to help stimulate healthy protein production in association to the retina. Vectors are commonly used to express non-mutated genes in photoreceptors or other types of retinal cells.
The human eye is one of the most sensitive and nerve-packed part of the body.
Usually the first sign of symptoms is worsening of night vision as some photoreceptors start to degenerate, followed by loss of peripheral vision, and then before blindness, central vision is spared the longest (Busskamp et al., 2011). Another symptom is the appearance and constriction of the hyperautofluorescent ring of the retina, which is a ring of abnormal light emission from the accumulation of a substance called lipofuscin. The ring, in most RP patients appears to constrict and decrease in diameter, an indicator for a retina’s change in structure, which usually occurs in retina affected by RP (Lima et al., 2012). In order to have RP, one must have mutations in their genome that lead to either a lack of required protein, creation of toxic proteins, or abnormalities in the structure of essential proteins. All of these causes lead to a thinning of the retina (Corn, n.d.). Photoreceptors in the outer retina start to degenerate and rod cells are usually the first to completely stop functioning. On the other hand, cone cells survive much longer and can play an important role to prolonging vision and since they survive longer, the rod to cone ratio usually increases drastically (Mundy et al., 2016).The idea of transneuronal degeneration explains how nearby nerve cells degenerate when there is a disruption of input or output of other neural cells and is one of the causes of
Some basic and primary approaches to RP would be to take medication to slow down the degeneration of retinal cells. It is popular for people to try and amplify vision by using devices if the patient is not completely blind (Barrett, Berlinguer-Palmini, & Degenaar, 2014; Corn, n.d.; Smith et al., 2011). Electronic implants are also used to try and restore vision, and focus more on changing extracellular currents, moving ions away from or towards photoreceptors to change tonicity or the cell and thus polarity (Trenholm & Roska, 2014). Some scientists aim to restore vision without the dependence on devices, at least temporarily as of now. Since photoreceptors are the cells that are degenerated most often, the most direct ways of vision restoration would be through implanting photoreceptors by taking advantage of vectors, utilizing electronic retinal implants which increase light sensitivity, or implanting genetically encoded light sensors to make cells light responsive, also known as gene supplementation (Busskamp et al., 2011). Much research has been devoted on gene