Gene could hold key to treating deafness
Scientists have identified a gene that, when deleted, causes deafness in mice. The findings explain why mutations in the gene are associated with inherited deafness in people and could lead to new treatments.
Studies of deafness in families linked the gene FGF20 to the condition, but scientists were unsure of its exact role. To answer this question they deleted the gene in mice.
The researchers found that this resulted in healthy but completely deaf mice. When they examined the inner ear of the mice they found that they were lacking outer sensory hair cells, which amplify sound. However, inner sensory hair cells, which are responsible for transmitting sound to the brain, were not affected.
This is significant because most age- and noise-related deafness is linked to loss of outer sensory hair cells.
The research also showed that FGF20 is required for the development of the outer but not the inner sensory cells and that this must occur within the first 14 days of embryo development in mice. Possible future treatments could reactivate FGF20 to generate new sensory hair cells.
With around two in every 1000 children being born with inheritable deafness and age-related-deafness affecting one in three people over the age of 65, these findings could help millions who suffer from hearing loss.
See also the AnimalResearch.info page on deafness