Gene-based therapy targeting proteins that are directly involved in the initial growth of the stereociliary bundles of cochlear hair cells has mainly focused on harmonin, whirlin, and clarin-1, which lead to different forms of Usher syndromes when mutated (Usher 1C, Usher 2, and Usher 3A, respectively).65 This evidence concerns the gene CLRN1 and Usher syndrome.