We all know that injuries, noise exposure and selected illnesses can result in hearing loss, but are your genes involved? The answer to this question is ‚Yes. Genetic abnormalities actually lay at the root of most forms of hearing loss. Furthermore, developmental experts consider genetic hearing loss to be the most common birth defect in developed countries.
Essential genetics. Our is DNA composed of genes, which behave like little pieces of code that, when set in a specific combination, cause us to look and function the way we do. Scientists have discovered over 100 genes that can impact hearing. Hearing loss may result from any one of these genes being missing or altered. These irregular gene sequences are handed down through families from parents to their children.
Categories of genetic hearing loss. Genetic hearing loss can affect the inner ear, outer ear or both. Conductive, sensorineural or mixed hearing loss may result. Besides that, some genes may cause hearing loss before a child learns to talk (prelingual hearing loss), and other genes cause hearing impairments that appear after speech is learned (postlingual hearing loss). One of the more common conditions to affect hearing is Usher syndrome, a condition that is thought to afflict over 50% of deaf-blind individuals according to the National Institutes of Health. Another common genetic condition is Waardenburg syndrome, a disorder in which hearing loss occurs in the inner ear but outer effects such as light skin, light eyes and a white flash of hair may be also be seen.
The good news about genetic hearing losses. Fortunately, hearing loss is not necessarily passed from parent to child. The genes that contribute to hearing loss are usually recessive and therefore often don’t lead to any outward symptoms because the child has received a normal copy from the other parent. Since there are hundreds of distinct genes linked to hearing loss, even if both parents are hearing impaired, their children may not be since the parent’s hearing loss can have different underlying causes. Genetic screening is available for individuals who suspect hearing loss is in their genes.