In the journal Nature, Professor David Liu and his colleagues report that one injection of a “genome editing cocktail” prevented hearing loss in young mice that would otherwise have gone deaf.
Half of all cases of deafness have a genetic root, but treatment options are limited. In this case, scientists focused on TMC1 gene mutation, which triggers the loss of ciliated cells in the inner ear. By destroying the mutated copy of the gene in mice using CRISPR Cas9, they were able to maintain a certain level of hearing in the animals. The delicate stage involves directing CRISPR towards the mutated version of the gene as opposed to its normal copy. To do this, they packaged the Cas9 enzyme and guide RNA into a greasy bundle that “slips” between the cells.
Scientists still have a long way to go before trying this approach in humans but they are already recommending an injection during childhood, before the loss of ciliated cells in the inner ear becomes irreversible.
Medical press, Howard Hughes (20/12/2017)