Meet Opal Sandy, an 18-month-old from Oxfordshire, England, who was born deaf due to a condition called auditory neuropathy. Opal became one of the first recipients of a pioneering gene therapy treatment aimed at restoring her hearing.Under anesthesia, Opal received the treatment in her right ear, along with a cochlear implant in her left ear. The results were astonishing. Within weeks, she could detect loud noises, and now, just six months later, she can hear whispers and is speaking her first words like mama, dada, and uh oh.Opal's deafness stemmed from a genetic condition called DFNB9, a common form of inherited deafness caused by the body's inability to produce otoferlin – a protein crucial for transmitting sound signals to the brain.In a groundbreaking trial, four other children – two girls and three boys – also born deaf due to DFNB9, received the same gene therapy. The results were extraordinary – they regained hearing in both ears, could hear and speak words, and even locate where sounds were coming from. Two children showed exceptional progress, responding to the complexities of music.So how does this therapy work? It uses a harmless virus to deliver a healthy copy of the OTOF gene responsible for hearing. Delivered via an inner ear infusion, the treatment was well-tolerated with no major side effects.The children were monitored for six months in Shanghai, China, and while the trial continues, the results highlight the therapy's promise for wider application.Dr. Zheng-Yi Chen, a Harvard researcher, expressed excitement about the astounding results, noting continued hearing improvements in treated children. He emphasized the benefits of treating both ears for better speech understanding and sound localization.Dr. Chen said, Our goal is to help regain hearing, no matter the cause. Our study supports treating DFNB9 in both ears, and we hope this approach can expand to other genetic or non-genetic deafness causes.Researchers stress the importance of binaural treatment for three-dimensional hearing, crucial for communication and activities like driving. Published in Nature Medicine, the study paves the way for larger international trials.