A new study published October 7 finds that experimental gene therapy combined with special goggles can restore limited visual function in some people with advanced inherited blindness.
Scientists have made progress in restoring some visual function to people who are blind due to genetic disorders. The condition known as retinitis pigmentosa causes degeneration of the light-sensing cells in the retina.
In a new study researchers used a gene therapy approach that involved injecting a harmless synthetic virus into the eye according to The Guardian. This injection carried genetic instructions to produce a light-sensitive protein in surviving retinal ganglion cells according to a report from Science News.
Patients also wore special goggles that helped them detect and locate objects like a notebook or a doorway. The treatment improved light sensitivity in seven of ten participants according to findings published in the New England Journal of Medicine. Six participants experienced improvements considered clinically meaningful.
This work builds on an earlier success from 2021 where one patient was able to see and count objects. The technique is called optogenetics which uses genetic changes to make cells respond to light. Rather than fixing the damaged light detectors in the retina this method gives retinal ganglion cells the ability to sense light.
The goggles used a camera to detect brightness changes and then projected those as pulses of amber light onto the retina. Participants were able to find doorways or spot objects but could not yet read words or recognize faces.
The research team hopes to improve the treatment so that it can help with more complex visual tasks in the future. One limitation is that this approach only works if the optic nerve is still functional.
The therapy was tested on people with advanced retinitis pigmentosa caused by inherited genetic mutations. Although there is no cure for this condition researchers are exploring ways to slow its effects and preserve vision.
The study was led by José-Alain Sahel of the University of Pittsburgh and Botond Roska of the Institute of Molecular and Clinical Ophthalmology Basel. They injected genetic instructions for a light-sensitive protein into the eye which came from algae. This made the retinal ganglion cells sensitive to amber light and allowed patients to react to visual cues.
The treatment has shown improvements that remained measurable over months to several years in some individuals. Patients reported being able to detect objects but not faces or detailed images.
The research team continues to work on improving the therapy for more advanced visual tasks.
This is part of a longer-term effort to help people with degenerative eye diseases regain some sight.
IMAGE: Source Retinitis pigmentosa by Christian Hamel Author Christian Hamel Permission (Reusing this file) © 2006 Hamel; licensee BioMed Central Ltd. CC2