A new gene therapy is giving people born deaf the chance to hear, often within just weeks. In a small but groundbreaking study, researchers delivered a working copy of a key hearing gene directly into the inner ear using a single injection. All ten patients, ranging from young children to adults, experienced improved hearing, with some showing rapid gains in just one month.
Source: Deafness reversed: One injection restores hearing in just weeks
For one cause of deafness, but still, pretty amazing.