A new genetic study carried out by researchers at the Johns Hopkins University School of Medicine, Maryland, has identified a pair of proteins that precisely control when sound-detecting cells, known as hair cells, are born in the mammalian inner ear.
The study published in the latest issue of the eLife journal, reported that the findings may hold a key to future therapies to restore hearing in people with irreversible deafness.
Hearing is based on two types of sound-detecting cells, inner and outer hair cells, which convey sound information to the brain. Unlike their counterparts in other mammals and birds, human hair cells cannot regenerate. So, once hair cells are damaged, hearing loss is likely permanent. Problems with hair cells are responsible for 90 percent of hearing loss.
The first step in hair cell birth starts during the fetal development. Here, the immature cells found in the outer cochlea transform into fully mature hair cells. Then, the cells’ production moves from the outer cochlea to the inner ear.