DNA strand representing discovering genes that cause hearing loss.

 

When you hear about medications that restore hearing, what’s your first thought?

It’s too good to be true? It’s another brand making false promises? It can’t possibly work? Given the dangerous hearing remedy myths out there, it’s good to have some healthy skepticism.

In this case, though, there is a promising hearing loss drug therapy in early stages of research. Here’s more about who it might help and how long it’s likely to take to hit the market.

Breakthroughs in Genetic Science

Since the identification of DNA structure in the 1950s, researchers have been fascinated with our genetic makeup. Over the many decades of discovery since, scientists have learned that DNA is why one person has blue eyes and another has brown. Your general height, aspects of your personality and even predisposition to certain diseases can often be mapped out in the genes that make up your DNA.

There’s still a lot the genetic researchers don’t know. And applying the knowledge to create treatments is still in its infancy. But as we learn more, we’re beginning to see researchers asking important questions.

What’s the genetic component of hearing loss? Could we develop treatments to address that specific gene?

A Genetic Look at Hereditary Hearing Loss

Congenital hearing loss can be the result of genes passed down from the parent. In some cases, a baby may not be born with DNA that will lead to hearing loss, but a mutation occurs in a baby’s DNA while they’re developing in the womb.

Researchers at the University of Iowa Laboratory of Human Molecular Genetics have previously been able to locate the LMG2 family of genes, which are responsible for deafness passed down through the family. Later the same team was able to further narrow the culprit to a mutation in a certain part of the chromosome called DFNA27.

The final stage was to isolate the specific gene causing the hearing loss. It’s known as the REST gene. Once isolated, these scientists began looking for possible drug therapies to alter this gene.

A Possible Genetic Treatment

Researchers have already been able to restore low-frequency hearing in mice using this new genetic treatment. Humans, like mice, hear sound in many different frequencies (pitches).

Frequency isn’t volume. It’s how fast sound waves hit your ears. These frequencies make up the complexity of sound.

They help you determine if your son is saying “Bog” or “Dog” as the two of you enjoy Sunday afternoon conversations. Frequency helps you distinguish between your cat’s meow and the cry of a neighbor’s child when he stubs his toe on the sidewalk outside your home.

Without frequency, you wouldn’t be able to enjoy the subtle tone changes in music or a singer’s voice.

Restoring low frequency in mice means that the mice can now more clearly hear and understand sounds at a low pitch. This is a partial restoration of hearing that could potentially advance to a wider range of frequencies.

They did this by finding a way to “turn on” and “off” part of the REST genes. When it’s on, it protects the inner ear’s sensory hair cells responsible for hearing. When it’s turned off, deafness occurs.

How This May Be Used to Treat Hearing Loss

Human trials are likely well down the road. The FDA requires extensive testing before something like this is made available to the general public. The FDA has to make sure, for example, that there are no potential side effects that cause more harm than good. Experts will need to work all that out to ensure public safety.

If and when this genetic drug treatment is approved by the FDA, this may be a way to restore partial hearing in those with hereditary hearing loss, or they may be able to prevent some congenital hearing loss at birth.

As the drug therapy improves, it could also demonstrate that it can prevent or slow down age-related hearing loss. Since this gene has been shown to improve the survival of the tiny hair cells in the inner ear that pick up sound, manipulating it may reinforce these very delicate cells. They do not regenerate if damaged, so preserving them is essential to preventing hearing loss.

We look forward to seeing how this research develops and discussing it here on Helping Me Hear. Because it may be decades away, it’s important to consider what you can do now to slow the progression of age-related hearing loss. Most importantly, that’s seeing a hearing specialist and wearing your hearing aids.