Reviving Hair Cells and Hearing

More and more of us either have or will have hearing problems. In fact the number of Americans with hearing loss has nearly tripled in the last forty years to 36 million.

Now, gene therapy to the rescue. In this case a gene called Math1 has been used to generate new hair cells inside a guinea pig's inner ear known as the cochlea. For us, those tiny hairs pick up sound vibrations to allow us to hear.

One reason why more Americans are facing hearing loss is prolonged exposure to loud noises. I hate to sound like an old guy but loud music is usually the problem.

People are blasting music in their cars and iPods which over time wears out the tiny hairs in the cochlea that pick up sound vibrations.

This type of hearing loss is called sensorineural which is damage to the cochlea or to the nerve pathways from the inner ear to the brain. The result is a reduction in sound level and difficulty hearing faint sounds. But a person can also have trouble understanding speech.

The goal of this latest study is to reverse the damage by growing new hairs using the Math 1 gene. Scientists did this with guinea pigs that had hearing loss.

They genetically modified the hair cells to make more of the math one protein.

Sure enough, the modified hair cells made more of it. And even though the higher protein levels were temporary, new hairs cells grew to replace those that were damaged and they were permanent.

The catch is you'd have to treat the ear within ten days of the damage. So the challenge now is to figure out how to grow the hair cells long after the damage was done.

Until then... we'd suggest turning down the volume and spending less time blasting your ears.