Researchers identify gene mutation linked to old age hearing loss

October 25, 2012

University of South Florida researchers have identified a genetic biomarker for age-related hearing loss, a major breakthrough in understanding and preventing a condition of aging that affects 30 million Americans and greatly diminishes their quality of life.

In a nine-year study that was a collaboration between USF's Global Center for Hearing & Speech Research and the National Technical Institute for the Deaf at the Rochester Institute of Technology, researchers were able to identify the first genetic biomarker for presbycusis. The genetic mutation carried by those who ultimately suffer from age-related is linked to speech processing abilities in older people.

Their findings are published in the journal Hearing Research. The study was authored by USF College of Engineering professors Robert Frisina Jr. and Robert Frisina Sr., the founders of the Global Center for Hearing & Speech Research, and David Eddins, a USF associate professor of communication sciences and disorders and chemical and biological engineering.

In collaboration with the House Ear Institute in Los Angeles, the researchers discovered a gene that produces a key protein in the inner ear – the cochlea – called glutamate receptor metabotropic 7 (GRM7). The GRM7 protein is intimately involved in converting sound into the code of the nervous system, in the cochlea, which is then sent to the parts of the brain used for hearing and speech processing.

The video will load shortly

Now having identified the gene, the researchers said people can be tested and takes steps earlier in life – such as avoiding loud noises, wearing ear protection and avoiding certain medicines known to damage hearing – to protect their hearing.

"This gene is the first genetic for human age related hearing loss, meaning if you had certain configurations of this gene you would know that you are probably going to lose your hearing faster than someone who might have another configuration," said Robert Frisina Jr.

The Frisinas launched their study of genetics' role in hearing loss nine years ago in hopes of identifying the cause of one of the most common forms of permanent hearing loss. Clinically, age-related hearing loss has been defined as a progressive loss of sensitivity to sound, starting at the high frequencies, inability to understand speech, the lengthening of the minimum discernible temporal gap in sounds, and a decrease in the ability to filter out background noise. Researchers now know the causes of presbycusis are likely a combination of multiple environmental and genetic factors.

"Age-related hearing loss is a very prevalent problem in our society. It costs billions of dollars every year to manage and deal with it. It's right up there with heart disease and arthritis as far as being one of the top three chronic medical conditions of the aged," said Robert Frisina Jr.

DNA analyses were conducted and completed at the University of Rochester Medical School and the Rochester Institute of Technology.

The study involved 687 people who underwent three hours of extensive examination of their hearing capabilities, including genetic analyses and testing of speech processing.

Interestingly, the gene mutation played out differently in women than in men, the researchers found. While the variation had a negative impact for men, it did the opposite for women, who actually had better than average hearing in their elder years. That discovery supports a 2006 finding by the Frisina research group that the hormone aldosterone plays a role in hearing capabilities.

Explore further: Novel genetic loci identified for high-frequency hearing loss

More information: www.sciencedirect.com/science/ … ii/S0378595512002092

Related Stories

Novel genetic loci identified for high-frequency hearing loss

April 26, 2012
The genetics responsible for frequency-specific hearing loss have remained elusive until recently, when genetic loci were found that affected high-frequency hearing. Now, a study published today in the open access journal ...

Recommended for you

Dulled taste may prompt more calories on path to obesity

July 28, 2017
Cornell University food scientists have found that people with a diminished ability to taste food choose sweeter - and likely higher-calorie - fare. This could put people on the path to gaining weight.

Artificial light from digital devices lessens sleep quality

July 28, 2017
There's no doubt we love our digital devices at all hours, including after the sun goes down. Who hasn't snuggled up with a smart phone, tablet or watched their flat screen TV from the comfort of bed? A new study by researchers ...

Study finds walnuts may promote health by changing gut bacteria

July 28, 2017
Research led by Lauri Byerley, PhD, RD, Research Associate Professor of Physiology at LSU Health New Orleans School of Medicine, has found that walnuts in the diet change the makeup of bacteria in the gut, which suggests ...

Sugar not so sweet for mental health

July 27, 2017
Sugar may be bad not only for your teeth and your waistline, but also your mental health, claimed a study Thursday that was met with scepticism by other experts.

Could insufficient sleep be adding centimeters to your waistline?

July 27, 2017
Adults in the UK who have poor sleep patterns are more likely to be overweight and obese and have poorer metabolic health, according to a new study.

Vitamin E-deficient embryos are cognitively impaired even after diet improves

July 27, 2017
Zebrafish deficient in vitamin E produce offspring beset by behavioral impairment and metabolic problems, new research at Oregon State University shows.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.