Everyone knows that noise, injuries and certain diseases can result in hearing loss, but are there also genetic factors involved? The simple response to this question is “Yes.” In fact, industry professionals agree that most hearing loss is caused by some kind of genetic irregularity. Furthermore, developmental experts consider genetic hearing loss to be the most frequently occurring birth defect in developed countries.
DNA, genes and inheritance. They way your body looks and functions is controlled by the genetic code of your DNA – your genes. Scientists have discovered more than 100 genes that can impact hearing. Hearing loss may result from any one of these genes being missing or altered. When an individual having these irregular gene sequences has a child, the abnormal gene or genes can be passed down to the child too.
Genetic hearing loss categories. Some forms of genetic hearing loss can visibly affect the outer ear, while other forms just influence hearing in the inner ear. Conductive, sensorineural or mixed hearing loss may result. What’s more, genetic hearing loss can present itself at birth or later in life. A few of the genetic conditions are prevalent enough to have names. For example, Usher syndrome affects about 50 % of the deaf-blind population. Another named condition that includes hearing loss is Waardenburg syndrome. Distinguishing characteristics include streaks of white hair, pale skin and light-colored eyes in addition to the hearing loss.
Will children inevitably inherit hearing loss? While it’s true that parents with hearing loss genes may pass them on to their children, it does not necessarily mean that the children will have a hearing problem. The genes that contribute to hearing loss are typically recessive and therefore frequently don’t result in any outward symptoms because the child has received a normal copy from the other parent. It’s not unusual for the children of hearing impaired parents to have normal hearing. Because there are hundreds of genes involved in hearing, it is more likely than not that the parental hearing losses do not share the same cause. Genetic testing is available for families who believe hearing loss is in their genes.