Gene therapy restored colour vision to colourblind children with the inherited retinal disorder achromatopsia, in the first trial of its kind in two paediatric patients.
The finding shows that gene replacement therapy in achromatopsia can awaken dormant cone-signalling pathways if used within the most plastic period of brain development – during younger years.
Achromatopsia is a severe monogenic heritable retinal disease that disrupts cone function from birth, leaving patients with complete colour blindness, low acuity, photosensitivity and nystagmus.
The patients underwent functional magnetic resonance imaging with a novel mapping approach that separated emerging post-treatment cone signals from existing rod-driven signals in patients, allowing the researchers to pinpoint any post-treatment changes in visual function directly to the targeted cone photoreceptor system.