In October 2023, 11-year-old Aissam Dam heard noise for the first time. He’s the first patient in the United States to receive gene therapy for genetic hearing loss.
While many people lose hearing over time, Aissam had congenital deafness. That means he was born deaf. About one of every 1,000 babies has congenital deafness. In his inner ear, Aissam had a mutated otoferlin gene. About 200,000 people suffer from this type of deafness.
What does otoferlin do? God designed our ears in such a way that each tiny part has a role to play and must function properly. When sound enters your ears, it comes in as waves. Those waves travel into the cochlea, the part of the inner ear that looks like a snail shell. Fluid in the cochlea carries the sound waves. They make ripples in the fluid. Those ripples send messages to the brain through thousands of tiny hairs in your inner ear. This is where otoferlin comes in. Without otoferlin, the hairs aren’t triggered to send the messages to the brain. It’s a bit like putting a letter in the mailbox. Without the mail carrier (otoferlin), the letter (sound) isn’t going anywhere.
Treating this type of deafness is more simple since otoferlin is the only part that’s not working properly. Doctors inject a harmless virus that carries a working copy of the otoferlin gene into the cochlea. Once inside, the gene encourages the ear to make more otoferlin. This stimulates the tiny hairs to pass along the message to the brain.
Right now, four other teams of scientists are working on clinical trials to treat deafness caused by missing otoferlin. Scientists in China reported successfully treating five children last year.
Until these trials, many doctors considered genetic deafness uncurable. Devices like cochlear implants—a type of hearing aid—can be very helpful. Like eyeglasses which help make sight clearer, cochlear implants assist with hearing. But neither device actually heals. Cochlear implants also change the shape of the inner ear, making it tricky to perform the gene therapy on people who already have the implant.
Aissam never received a cochlear implant. He was a perfect candidate for otoferlin treatment. Doctors hope the lessons they’ve learned will help them use gene therapy to target other types of hearing loss.
Aissam’s hearing isn’t fully restored. He hears muffled noises and will still need to rely on sign language to communicate. Others’ speech remains muted, but he can now hear his father’s voice.
by Bekah McCallum, in Duluth, Georgia
Why? God who designed ears for hearing also mercifully gives doctors the resources to bring progress toward healing. But He alone can heal us completely—physically and spiritually. See Mark 7:31-37.
