Hearing Loss May Have Genetic Cause

A set of gene mutations that cause progressive hearing loss have been identified by Michigan State University (MSU) researchers.

The study, which may provide important clues for scientists trying to better understand acquired hearing loss, appears in the November issue of the American Journal of Human Genetics.

The MSU team focused on a gene called DFNA 20, which is known to play an essential role in the structure of the inner ear, the cochlea. The gene is also one of almost 100 that are known to play a role in hearing loss.

"Until now, no mutations have been discovered in this gene, so this finding is expected to provide new insight that will help researchers understand more about the biology of progressive (hearing) loss," Rachel Fisher, director of the MSU Hearing Research Center, says in a prepared statement.

"One possibility is that the mutations (in the DFNA 20 gene) interfere with processes that allow ears to repair damage done by noise or aging," Fisher says.
Karen Friderici, MSU associate professor of microbiology and molecular genetics, adds: "Knowing what the gene is means that you can maybe move toward preventing hearing loss or, possibly curing it."

It's estimated that about 28 million Americans, including one in three over age 60, have hearing loss. But little is known about how the hearing mechanism is affected by aging.