Researchers identify gene mutation that causes rare form of deafness

Jul 12, 2010

Researchers have identified a gene mutation that causes a rare form of hearing loss known as auditory neuropathy, according to U-M Medical School scientists.

In the study published online today in the USA, U-M's Marci Lesperance, M.D., and Margit Burmeister, Ph.D. led a team of researchers who examined the DNA of individuals from the same large family afflicted with the disorder.

The researchers identified a mutation in the DIAPH3 gene that causes over-production of a compound known as a diaphanous protein. In previous studies, hearing loss has been linked to a related gene that also affects a diaphanous protein.

Currently, diagnosing auditory neuropathy requires specific testing. Auditory neuropathy may be unrecognized if testing is not performed early in life.

"Since we previously knew of only two genes associated with auditory neuropathy, finding this is significant," says Lesperance, professor in U-M's Department of Otolaryngology and chief of the Division of Pediatric Otolaryngology.

"This discovery will be helpful in developing genetic tests in the future, which will be useful not only for this family, but for all patients with auditory neuropathy," Lesperance says.

To investigate the role of these compounds in auditory function, the authors engineered a line of that expressed an overactive diaphanous protein in the insects' auditory organ. Using sound to induce measurable voltage changes, Frances Hannan of New York Medical College determined that the flies' hearing was significantly degraded compared to normal flies.

Burmeister says finding the genes causing such rare disorders is very difficult because researchers cannot look at many different families, and instead have to rely on a single family that is often not large enough. But in this study, the researchers used a multi-pronged approach. Rather than relying purely on genetic inheritance information, they combined this information with biological function regarding gene activity.

"The approach we used here of combining with functional information can be applied to identify the culprit genes in many other rare genetic diseases that have so far been impossible to nail down," says Burmeister, professor of Psychiatry and Human Genetics.

"We can now say we have a tool by combining several genomic approaches to find these genes."

Explore further: Mutation disables innate immune system

More information: Journal reference: www.pnas.org , Article number 201003027

Related Stories

Memory impairment associated with sound processing disorder

Jul 21, 2008

Mild memory impairment may be associated with central auditory processing dysfunction, or difficulty hearing in complex situations with competing noise, such as hearing a single conversation amid several other conversations, ...

Recommended for you

Mutation disables innate immune system

1 hour ago

A Ludwig Maximilian University of Munich team has shown that defects in the JAGN1 gene inhibit the function of a specific type of white blood cells, and account for a rare congenital immune deficiency that ...

Study identifies genetic change in autism-related gene

19 hours ago

A new study from Bradley Hospital has identified a genetic change in a recently identified autism-associated gene, which may provide further insight into the causes of autism. The study, now published online in the Journal of ...

NIH issues finalized policy on genomic data sharing

Aug 27, 2014

The National Institutes of Health has issued a final NIH Genomic Data Sharing (GDS) policy to promote data sharing as a way to speed the translation of data into knowledge, products and procedures that improve health while ...

The genes behind the guardians of the airways

Aug 27, 2014

Dysfunctions in cilia, tiny hair-like structures that protrude from the surface of cells, are responsible for a number of human diseases. However the genes involved in making cilia have remained largely elusive. ...

User comments : 0