New gene therapy improves vision in blind mice

biotech healthcare

Successful gene therapy trial in patients with X-linked Chronic Septic Granulomatosis The single AAV gene therapy platform combines CRISPR-Cas9 technology with micro-homology-mediated end joining. These two thing act essentially as genetic scissors and genetic glue respectively. Researchers can target a specific defective gene, cut it out and glue in a healthy replacement. In blind mice, this approach rescued approximately 10% of photoreceptors, resulting in improved light sensitivity and an increase in visual activity. The improvement in vision was about the same result gene supplementation can produce. "By treating mice blinded by inherited retinal degeneration with the new treatment, we show that a robust visual restoration can be achieved at a level similar to that mediated by conventional gene supplementation, assuring its potential for clinical application," Nishiguchi said. "The platform paves the way for treating patients with mutations in larger genes, which comprise the vast majority of those with inherited retinal degeneration. Furthermore, a similar approach can be applied to treat almost any ocular and non-ocular inherited conditions." Now, the researchers are applying the new genome editing platform to develop a therapy for human patients with retinitis pigmentosa, a group of rare conditions that can cause loss of peripheral vision and difficulty seeing at night. They will target common mutations among patients that remain untreatable by conventional gene therapy. Nishiguchi's team plans to have therapy in a clinical trial by as early as 2025. Source: Tohoku University Journal reference: Nishiguchi, K.M., et al. (2020) Single AAV-mediated mutation replacement genome editing in limited number of photoreceptors restores vision in mice. Nature Communications . doi.org//10.1038/s41467-019-14181-3 .