The successful restoration of hearing in mice suffering genetic form of deafness with the help of gene therapy has opened doors for researchers to try the same on humans.
Jeffrey Holt of Boston Children’s Hospital and Harvard Medical School said that their gene therapy protocol wasn’t ready yet for clinical trials as they needed to tweak it a bit more but in the not-too-distant future he thinks it could be developed for therapeutic use in humans.
The researchers tested gene therapy in two types of mutant mice. One type had the TMC1 gene completely deleted and is a good model for recessive TMC1 mutations in humans: Children with two mutant copies of TMC1 have profound hearing loss from a very young age, usually by around 2 years.
In the recessive deafness model, gene therapy with TMC1 restored the ability of sensory hair cells to respond to sound producing a measurable electrical current and also restored activity in the auditory portion of the brainstem.
In the dominant deafness model, gene therapy with a related gene, TMC2, was successful at the cellular and brain level, and partially successful at restoring actual hearing in the startle test.
Holt said that he could envision patients with deafness having their genome sequenced and a tailored, precision medicine treatment injected into their ears to restore hearing.
The study is published in the Journal Science Translational Medicine.