Undoubtedly injury and illness can cause hearing loss, but could genetics also contribute? The answer to this question is “Yes.” When you look at the data, genetic factors are actually the main category of hearing losses. Additionally, hearing loss is considered the most common birth defect in the developed world.
A primer on genetics. Genes are basically pieces of code that make up our DNA and tell our bodies what to do and how to look. Researchers have identified over 100 genes that can negatively affect hearing. If one or even more of these genes is changed or missing the effect is often hearing loss. Parental genes are passed to children, so any irregular gene sequences which produce hearing loss are handed down.
Genetic hearing loss variations. Genetic hearing losses can stem from flaws in the inner ear, outer ear or both areas. The hearing loss can be sensorineural, conductive or mixed. Note that, hereditary hearing loss can present itself at birth or later in life. One of the most 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. Waardenburg syndrome is another common disorder that affects hearing in the inner ear but also causes pale skin, a streak of white hair, and light or multi-colored eyes.
Will children inevitably inherit hearing loss? While it’s true that parents with hearing loss genes may pass them on to their kids, it doesn’t necessarily mean that the children will have a hearing problem. Most genes related to hearing loss are recessive, which means that even though an individual has an irregular gene, that gene won’t always cause a problem so long as a normal copy is inherited from the other parent. Because there are hundreds of distinct genes linked to hearing loss, even if both parents are hearing impaired, their kids may not be since the parent’s hearing loss could have different root causes. For parents concerned about a family history of hearing loss, genetic testing and counseling is available.