Restoring hearing in mice

Yeh, W-H. et al. Sci. Transl. Med. 12, eaay9101 (2020)

Genetic defects are a major cause of hearing loss (HL) in newborns. No curative treatments are available for genetic HL, but gene therapy-based strategies that replace an absent gene product or silence a pathological allele have shown promising results in mouse models.

A study describes a new base-editing approach aimed at correcting a point mutation in Tmc1 that causes deafness in Baringo mice. Adeno-associated virus (AAV) delivery of a cytosine base editor and guide RNA into the inner ears of Baringo mice at postnatal day 1 successfully corrected the Tmc1 mutation and partially rescued auditory function, thereby demonstrating the potential of base editing as a treatment for HL caused by recessive loss-of-function point mutations.