Research has found that there are around one hundred genes that have been linked to the development of hearing loss in its carriers. Even a simple mutation of any of these genes can trigger hearing loss. These genes are either predominantly present in newborns, or tend to develop shortly after birth.
During the gestational period, hundreds of genes take part in developing the delicate cells within the ear and the part of the brain that is responsible for auditory interpretation. Even a tiny change during this developmental process can result in permanent hearing loss at birth. Even though research has only found a few over a hundred genes, it is thought that there are far more genes yet to be discovered that are related to hearing loss in humans.
Certain genes may have the ability to trigger hearing loss over time, especially with advanced age. Researchers are still conducting numerous studies to explore the effects of genetics on hearing loss.
Research studies explore participants across generations to examine the effects of hearing loss, not only in those who have it but also in those who don’t, so that they can compare which genes are different for their relatives with regular hearing. Once the differing genes are identified, they are studied in further depth to see what ways they affect human hearing and result in hearing loss.
Since it is difficult to find so many human subjects, researchers often use mice, since they have similar genetics to us when it comes to hearing. It was found that the majority of the genes that caused hearing loss in mice also tended to cause hearing loss in humans.
Research with mice revealed that the absence of certain genes give rise to hearing loss. In mice that were genetically modified to have a specific gene deleted (a gene thought to be linked to hearing loss), it was found that hearing loss did indeed occur in these mice.
Once the genetic link with the hearing loss in mice has been established, similar experiments are conducted on human beings to search for similarities. Even though the ethics of such experiments can be brought into question, they provide invaluable amounts of information that can bring major breakthroughs in the world of hearing loss in future.
