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.

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

Expert: Be concerned about how apps collect, share health data

October 20, 2017
As of 2016 there were more than 165,000 health and wellness apps available though the Apple App Store alone. According to Rice University medical media expert Kirsten Ostherr, the Food and Drug Administration (FDA) regulates ...

More teens than ever aren't getting enough sleep

October 19, 2017
If you're a young person who can't seem to get enough sleep, you're not alone: A new study led by San Diego State University Professor of Psychology Jean Twenge finds that adolescents today are sleeping fewer hours per night ...

Across Asia, liver cancer is linked to herbal remedies: study

October 18, 2017
Researchers have uncovered widespread evidence of a link between traditional Chinese herbal remedies and liver cancer across Asia, a study said Wednesday.

Eating better throughout adult years improves physical fitness in old age, suggests study

October 18, 2017
People who have a healthier diet throughout their adult lives are more likely to be stronger and fitter in older age than those who don't, according to a new study led by the University of Southampton.

Global calcium consumption appears low, especially in Asia

October 18, 2017
Daily calcium intake among adults appears to vary quite widely around the world in distinct regional patterns, according to a new systematic review of research data ahead of World Osteoporosis Day on Friday, Oct. 20.

New study: Nearly half of US medical care comes from emergency rooms

October 17, 2017
Nearly half of all US medical care is delivered by emergency departments, according to a new study by researchers at the University of Maryland School of Medicine (UMSOM). And in recent years, the percentage of care delivered ...

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.