Teacher: Jennifer Brakeman
A New Vision for the Future
…One such gene in particular is RPE65 which encodes for an enzyme that regenerates visual pigment after exposure to light and has been studied in detail (Bainbridge). A mutated RPE65 gene cannot make this crucial enzyme. Over time, photoreceptors will degrade, resulting in blindness. Unfortunately, there was nothing that could be done to alter the progression of the disease…
…But recently, clinicians have made significant research progress in this area and the eye disease is considered a good candidate for gene therapy (Ledford). Eye surgery is less complicated than in other organs because eye target cells are directly available for injection and corresponding surgical methods are relatively simple. Additionally, because of ocular immune privilege, they are less prone to immune responses after treated with biological reagents. Recently, scientists in the UK and the USA have reported success in treating people with RPE65 retinal dystrophy. Early tests were done mostly on animals followed by human clinical testing that have shown encouraging results (Beltran). The gene therapy treatment involves creating recombinant RPE65 encoding genes and inserting them into viral vectors, which are surgically injected near the retinal cells. The virus would migrate inside the cell and replicate the correct RPE65 genes in the process and make the needed proteins for the required photoreceptor enzymes of the retina…
…Recently, a study published in Nature noted that CRISPR has been successfully developed to treat retinitis pigmentosa in rats (Suzuki). Although they report that only about 5% of the targeted cells actually expressed the inserted genes, the results were considered very promising. Once CRISPR is shown to be safe, scientists foresee human clinical trials using CRISPR in about five years.