Hearing impairment and deafness are quite pervasive, and the numbers are quite startling. One out of every 200 children is born with hearing impairments, while one out of every thousand is born deaf, of which half are caused by a genetic mutation. Additionally, while there are options such as hearing aids and cochlear implants for individuals with impairments, there are currenttly no options for the deaf community.
A team of researchers led by Professor Karen Avraham of the Department of Human Molecular Genetics and Biochemistry at TAU's Sackler Faculty of Medicine and Sagol School of Neuroscience is looking to change that through their study of a gene therapy model that would inject a virus into the inner ear to deliver a functional copy of the mutated gene. This functional copy would replace the defective copy, and restore functionality. Using mouse models, the team specifically targeted SYNE4, a gene that causes a rare deafness and was discovered by their own lab a few years back. They developed a synthetic virus, and used it to deliver a good copy of SYNE4 to the inner ears of these mice. This therapy was administered shortly after birth, and hearing was monitored. Once this good copy was integrated, inner ear hair cells which are critical for hearing, was able to survive and function and treated moce developed normal hearing. In fact, this approach worked so well that the level of restored hearing almost rivaled individuals with normal hearing. With the promising results seen in this study, the team is starting to look at some of the other mutations that cause deafness.
What this means for Usher Syndrome: The experimental therapy in this study was administered shortly after the birth and therefore, likely not an option for us today. However, the results are extremely promising, and one day, we may be able to treat a newborn for deafness, enabling them to grow up with the gift of sound.