By Pesach Benson • September 14, 2026
Jerusalem, 14 September, 2026 (TPS-IL) — Israeli, Palestinian and US scientists working together have identified a gene essential for normal hearing in humans and mice, revealing a previously unknown mechanism by which a genetic defect can damage the inner ear.
The discovery could improve the diagnosis of inherited hearing loss by giving doctors another gene to examine in patients whose condition has no known cause. It also reveals a previously overlooked role for supporting cells in maintaining the inner ear’s structure, potentially helping researchers identify new targets for future treatments.
Tel Aviv University on March 15, 2021. Photo by Eitan Elhadez-Barak/TPS-IL
More than 1.5 billion people worldwide live with some degree of hearing loss, including 430 million with disabling hearing loss, according to the World Health Organization. Genetic factors account for a substantial share of hearing loss that begins in childhood.
“This work has demonstrated that global partnerships can drive meaningful scientific advances, helping to pave the way for future genetic therapies and interventions,” said Karen B. Avraham, Dean of the Gray Faculty of Medical and Health Sciences at Tel Aviv University and a senior author of the study. She led the research along with Moien Kanaan of Bethlehem University and Mary-Claire King of the University of Washington.
The study found that a gene called FMN1 helps maintain the microscopic structure of the cochlea, the part of the inner ear that converts sound into signals sent to the brain. Until now, FMN1 had not been linked to any human disease.
The discovery began with an extended Palestinian family in which several children were born with moderate hearing loss in both ears and light-colored hair. Genetic testing showed that the affected children had inherited two copies of a rare FMN1 variant that prevents the body from producing a functional form of formin-1, the protein made by the gene.
To understand how the genetic change caused hearing loss, the researchers studied mice that lacked functional formin-1. The mice developed hearing loss similar to that seen in the family.
The researchers then examined the mice’s inner ears under a microscope. They found that two types of supporting cells in the organ of Corti, the part of the cochlea that detects sound, had lost their normal structure.
How the Gene Damages Hearing
These cells normally contain tightly organized microscopic fibers that provide structural support and help the cochlea respond precisely to sound. Without functional formin-1, those structures became disorganized. The mice also had reduced activity in the auditory nerve, which carries sound information from the inner ear to the brain, as well as fewer nerve fibers.
The findings show that normal hearing depends on more than sound-sensing cells and nerves themselves. Supporting cells must also maintain a highly organized structure for the cochlea to function properly.
The study may also help explain why some members of the family had lighter-colored hair. Formin-1 is involved in transporting melanosomes, structures inside cells that contain the pigment responsible for hair and skin color. The researchers suggest that the same genetic defect may therefore affect hearing and pigmentation through separate biological processes.
The discovery adds FMN1 to the more than 200 genes known to be important for normal hearing.
The study was published in the peer-reviewed journal Proceedings of the National Academy of Sciences (PNAS).
