October 26, 2012
Discovery Of Gene Related To Hearing Loss
[ Watch the Video: Gene That Leads To Hearing Loss ]
Connie K. Ho for redOrbit.com — Your Universe Online
Researchers from the University of South Florida (USF) recently identified a gene related to hearing loss in older Americans. 30 million individuals in the U.S. suffer from hearing loss and the new findings will assist in the development of preventive efforts for this particular population.
The discovery of a genetic biomarker for age-related hearing loss is nine years in the making. Robert Frisina Sr. and Robert Frisina Jr., both of USF, were interested in finding out one of the causes of long-term permanent hearing loss. As such, the study became a collaborative effort between USF´s Global Center for Hearing and Speech Research and Rochester Institute of Technology´s (RIT) National Technical Institute for the Deaf.
In particular, the scientists identified a genetic biomarker for presbycuiss and the genetic mutation related to hearing loss can eventually affect a person´s ability to process speech. The researchers from USF and RIT worked with the House Ear Institute in finding a gene that creates an important protein in the cochlea, which is the inner ear. The protein, otherwise known as glutamate receptor metabotropic 7 (GRM7), helps convert sound into the code for the nervous system. The brain then utilizes that code for hearing and speech processing purposes.
“This gene is the first genetic biomarker 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,” explained Robert Frisina Jr., a professor at the USF College of Engineering, in a prepared statement.
The study included a DNA analyses by the University of Rochester Medical School and RIT. A total of 687 people participated in the study and completed three hours of examinations regarding their hearing abilities. Testing included observations of speech processing and analyses of genetic material.
The gene appeared to have different results from males and females. The gene ended up having a negative impact for men, but a positive impact for women who reported that they had a better than average hearing in their later years. The differences between males and females relates to a 2006 finding by the Frisina research group that stated that the hormone aldosterone affected hearing capabilities.
The researchers believe that the gene can help people understand how to protect their hearing. They noted that people can prevent hearing loss with little things like avoiding loud noises, particular medications know to cause hearing damage and wearing ear protection. The scientists now understood that presbycusis is caused by a number of different genetic and environmental 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,” noted Robert Frisina Jr., who also helped found the Global Center for Hearing and Speech Research, in the statement.
The results of the project were recently featured in the journal Hearing Research.