How a decades-long quest led to the first gene therapy for deafness caused by a mutation.
A home video from 2025 captures a toddler absorbed in play with a toy bulldozer. When an adult calls out “hello”, the boy turns his head. Another video filmed around nine months later shows the two-year-old dancing exuberantly to the song ‘I Just Might’ by pop star Bruno Mars, as the child sweeps his hand across a toy guitar in time to the beat. Such scenes might seem unremarkable, but a few months before the first video was recorded, the boy had been severely deaf, having been born with a rare form of hearing loss known as DFNB9 (autosomal recessive deafness 9). His hearing had been restored by an experimental gene therapy that is now approved for use in the United States.
Auditory neuroscientist and MBExC spokesperson Tobias Moser, who is a co-author of the Cell study, says that the work highlighted the OTOF gene as a potential target for gene therapy in humans. “By understanding the role of otoferlin, dissecting the disease mechanism and by demonstrating a relatively intact morphology of the cochlea, this made otoferlin a good target,” says Moser, who is based at the University of Göttingen in Germany.
Link to the Nature article
A confocal microscopy image of cochlear tissue from the inner ear shows cells successfully transduced by the viral vector Anc80L65, which carries a fluorescent marker that glows green.Credit: Lukas Landegger
