In a proof-of-concept study, researchers found evidence of the potential of base editors to correct mutations that cause inherited retinal diseases (IRD). IRDs are blinding conditions that are caused by mutations in genes. The base editors could restore visual function. The therapy uses a new generation of CRISPR technology. The new CRISPR technology could be an alternative to gene augmentation therapy. In previous CRISPR-Cas9 therapy, there were some challenges like unpredictable off-target mutations and low editing efficiency. In this newer form of CRISPR technology, it uses base editing with cytosine and adenine base editors. Base editors allow researchers to correct point mutations in a more precise and predictable manner which prevents some undesirable side effects. Mice with Leber congenital amaurosis, a type of IRD, caused by a mutation in the Rpe65 gene underwent base editing treatment. The treatment was able to restore retinal and visual function to near-normal levels. This proof-of-concept study provides evidence that base-editing technology could be a possible treatment for proteins affected by mutations that are related to vision.
What this means for Usher syndrome: As vision loss in Usher syndrome is caused by inherited retinal diseases, this proof-of-concept study opens the door for a new avenue of research for a possible treatment. This base editing allows for more targeted point mutation corrections that could repair proteins related to vision.