Gene Therapy Helps Adult Retinas Rebuild Damaged Connections in Landmark Study

A one-time gene therapy has helped damaged adult retinas rebuild important neural connections and recover visual function in a study that challenges the long-held belief that mature retinal tissue has little capacity for repair. Researchers at Michigan State University tested the treatment in dogs carrying a faulty CaBP4 gene, which disrupts calcium signalling between the eye’s light-sensing cells and the rest of the visual pathway, causing poor vision from early life. By delivering a healthy copy of the gene directly into the retina using a modified viral vector, the team not only improved vision — particularly in dim light — but also saw structural repair inside the eye, including expansion of the outer plexiform layer and growth of specialised synaptic ribbons that help transmit visual signals. Remarkably, these changes occurred in fully developed retinas and remained evident years after treatment, suggesting that adult retinal cells may retain more ability to reorganise and repair themselves than previously thought. The findings raise hope for future treatments for inherited retinal diseases and possibly other forms of neural damage, but the therapy has so far only been demonstrated in animals, and human clinical trials will be needed to establish whether it is safe and effective in people.