Stem cells cure deaf gerbils

The gerbils' hearing improved by 46 per cent on average. Photo / Thinkstock

Scientists tout major implications for treatment of humans with world-first study

Scientists have made a major breakthrough in the cure for deafness by restoring the hearing of deaf gerbils using human stem cells.

The technique, which is the first to use stem cells to treat deafness, could one day benefit hundreds of thousands of sufferers.

Researchers from the University of Sheffield were able to turn human embryonic stem cells into ear cells, which were then transplanted into the inner ear of gerbils that had been made deaf. On average, the deaf gerbils' hearing improved by 46 per cent, which in a human would mean the difference between not hearing a truck passing by, and being able to conduct a conversation at an indoor volume, the researchers said.

The gerbils, which were used because of the similarity between their hearing range and that of humans, underwent chemically-induced damage to one ear. Around 50,000 inner ear nerve cells were then implanted via a small incision behind the ear and a hole drilled into the base of the cochlea.

The technique could be used to cure a form of deafness known as auditory neuropathy, characterised by damage to the cochlear nerve, which links the inner ear to the brain. As many as 15 per cent of hearing problems are understood to be associated with auditory neuropathy, which is usually genetic but can also be exacerbated by factors such as noise exposure and jaundice at birth.

"This is an important step forward," said Dr Marcelo Rivolta, who lead the study. "We now have a method to produce human cochlear sensory cells that we could use to develop new drugs and treatments, and to study the function of genes. And more importantly, we have the proof-of-concept that human stem cells could be used to repair the damaged ear."

- Independent