An 11-year-old boy from Morocco has been cured of deafness through experimental gene therapy at the Children’s Hospital of Philadelphia (CHOP). The therapy targeted a rare gene mutation called otoferlin, which affects 200,000 people worldwide and destroys a protein necessary for transmitting sound to the brain. The breakthrough represents a major advancement in treating hearing loss caused by various genetic mutations. The boy, Aissam Dam, underwent a surgical procedure in October 2023, receiving a single dose of the gene therapy directly to his inner ear. Four months later, he can now hear sound for the first time in his life.