Scientists in Seattle are actively developing several different facets of gene therapy, including gene replacement and gene repair for SCID and related diseases. (fredhutch.org)
«Fountain - of - youth gene repairs tissue damage in adults.» (sciencedaily.com)
This is long enough to perform gene repair, but prevents cas9 from lingering in the cells and potentially disrupting other parts of the cells» genome. (sciencedaily.com)