In a landmark clinical trial, a new gene therapy appears to have given five children who were born deaf the ability to hear.
The trial, conducted in China by researchers from Harvard Medical School and the Massachusetts Eye and Ear Infirmary, treated six children ages 1 to 7 who were born completely deaf because of an inherited gene mutation.
In gene therapy, normal genes are inserted into cells to replace missing or defective ones.
Five of the six children showed robust progress after 26 weeks, able to understand and respond to speech or recognize speech in a noisy room. One child showed no change, although researchers are not sure why.
The trial focused on children with a particular condition called DFNB9, which renders sufferers totally deaf because of a mutation in the OTOF gene. This gene encodes a protein called otoferlin, which plays a role in transmitting sound to the inner ear. Without otoferlin, the sound signals never reach the brain. In this condition, the inner ear has no physical damage, according to the Harvard Gazette, and one single, simple gene mutation is responsible for deafness.
The technique may open the way for gene therapy for other forms of deafness.
