Stone's Hearing Aid Service

Where Your Hearing is Our Concern


Genetics of Hearing Loss

Posted on January 12, 2014 at 9:50 PM
Genetics of Hearing Loss 

Though inherited genetic defects are just one factor that can lead to hearing loss and deafness, which may occur at any stage of a person’s lifespan, this is often overlooked as one does not consider probability in this. 

50%-60% or 3 in every 1,000 infants born who suffer from hearing loss have obtained this through DNA. Although exact data is not available for the aging it is likely that genetics play an important role in hearing loss for the elderly as well. Other factors may include: medical problems, environmental exposure, trauma, and medications. 

Inherited genetic defects play an important role in congenital hearing loss. The majority of hearing loss is caused by mutations ("misspellings") in the DNA (deoxyribonucleic acid) sequence of genes. There are a number of other factors in the environment that can cause hearing loss too. 

25% or more of hearing loss in babies is due to "environmental” causes such as maternal infections during pregnancy and complications after birth.  Sometimes, both genes and environment work together as a team to cause hearing loss. For example, there are some medicines that can cause hearing loss, but only in people who have certain mutations in their genes. 

There are four compounds known as "bases" in a strand of DNA: adenine (A), guanine (G), thymine (T), and cytosine (C). Each DNA molecule consists of two strands that form the shape of a double helix, through the pairing of A with T, and C with G. Thus, knowing the sequence of bases on one DNA strand automatically gives the sequence on the other strand of the double helix. 

Genes contain the instructions that tell the cells of people’s bodies how to grow and work. For example, the instructions in genes control what color a person’s eyes will be. There are many genes that are involved in hearing. Sometimes, a gene does not form in the expected manner. This is called a mutation. Some mutations run in families and others do not.  If more than one person in a family has hearing loss, it is said to be "familial". That is, it runs in the family. If only one person in the family has hearing loss, it is called "sporadic". Meaning, it does not run in the family. About 70% of all mutations causing hearing loss are non-syndromic. This means that the person does not have any other symptoms. 

About 30% of the mutations causing hearing loss are syndromic. This means that the person has other symptoms besides hearing loss.  For example, some people with hearing loss are also vision impaired or blind. 

The cochlea (the part of the ear that changes sounds in the air into nerve signals to the brain) is a very complex and specialized part of the body that needs many instructions to guide its development and function. These instructions come from genes. Changes in any one of these genes can result in hearing loss. The GJB2 gene is one of the genes that contains the instructions for a protein called connexin 26; this protein plays an important role in the functioning of the cochlea. In some populations about 40% of newborns with a genetic hearing loss who do not have a syndrome, have a mutation in the GJB2 gene. 

Genetic forms of hearing loss must be distinguished from acquired (non-genetic) causes of hearing loss. The genetic forms of hearing loss are diagnosed by otologic, audiologic, and physical examination, family history, ancillary testing (e.g., CT examination of the temporal bone), and molecular genetic testing. Molecular genetic testing, available in clinical laboratories for many types of syndromic and nonsyndromic deafness, plays a prominent role in diagnosis and genetic counseling. 

Genetic  counseling: 
Hereditary hearing loss can be inherited in an autosomal dominant, autosomal recessive, or X-linked recessive manner, as well as by mitochondrial inheritance. Genetic counseling and risk assessment depend on accurate determination of the specific genetic diagnosis. In the absence of a specific diagnosis, empiric recurrence risk figures, coupled with GJB2 and GJB6 molecular genetic testing results, can be used for genetic counseling

Categories: Buy local By local, Hearing Health, Hearing Loss

Post a Comment


Oops, you forgot something.


The words you entered did not match the given text. Please try again.


Reply Normand
2:41 AM on October 29, 2022 
Reply kobe basketball shoes
10:19 PM on December 5, 2022 
Thank you for all of the hard work on this web page. Gloria loves participating in investigation and it's really easy to see why. I know all of the compelling manner you give very helpful steps on the blog and as well as attract response from other people about this theme then our princess is really being taught a lot. Enjoy the remaining portion of the new year. Your performing a great job.
kobe basketball shoes
Reply yeezy shoes
10:51 PM on December 5, 2022 
Thanks so much for giving everyone a very splendid opportunity to read critical reviews from this site. It is always so amazing plus packed with fun for me and my office fellow workers to search your website on the least 3 times weekly to find out the newest secrets you have got. And of course, I'm so always fulfilled concerning the perfect strategies you give. Selected two facts in this posting are undoubtedly the most impressive I've ever had.
yeezy shoes
Reply chrome hearts online store
11:29 PM on December 5, 2022 
I precisely had to thank you so much once more. I do not know what I would've used in the absence of the entire basics shown by you about such a subject matter. It had become a very frightful setting in my view, nevertheless taking note of a new specialized manner you solved the issue made me to cry over delight. I am just happy for your information and as well , have high hopes you are aware of a great job you were undertaking teaching other individuals via your blog. More than likely you have never come across any of us.
chrome hearts online store
Reply off-white
6:02 AM on December 6, 2022 
My wife and i got absolutely happy that Edward could conclude his analysis out of the ideas he obtained through the weblog. It's not at all simplistic just to find yourself freely giving key points which the rest could have been making money from. And we fully grasp we now have the writer to be grateful to for this. All of the illustrations you made, the easy site navigation, the friendships your site help to instill - it is most fabulous, and it's really facilitating our son and our family know that the article is amusing, which is exceedingly serious. Thanks for all!
Reply irving shoes
7:18 AM on December 6, 2022 
I'm just commenting to make you understand what a beneficial discovery my daughter obtained studying the blog. She picked up a wide variety of issues, with the inclusion of what it's like to possess a marvelous giving spirit to have most people very easily learn about chosen extremely tough topics. You really surpassed visitors' desires. I appreciate you for displaying these effective, healthy, revealing as well as fun tips on this topic to Janet.
irving shoes
Reply off white
9:13 AM on December 6, 2022 
My wife and i ended up being so contented that Edward managed to finish off his investigations by way of the precious recommendations he acquired from your very own blog. It's not at all simplistic to simply possibly be giving away tips and hints which often some people could have been trying to sell. And now we realize we have got the blog owner to be grateful to for this. These illustrations you have made, the easy web site navigation, the relationships you give support to foster - it's many incredible, and it's letting our son and us understand the article is awesome, and that is unbelievably fundamental. Thanks for the whole thing!
off white
Reply yeezy 500
9:23 AM on December 6, 2022 
Thank you so much for providing individuals with a very remarkable chance to discover important secrets from this site. It can be so beneficial and packed with fun for me and my office colleagues to visit your site more than 3 times weekly to read the newest issues you have. And definitely, I'm actually happy considering the breathtaking suggestions you serve. Certain 1 ideas in this article are indeed the most suitable we've had.
yeezy 500
Reply yeezy 350 v2
2:46 PM on December 6, 2022 
I needed to post you one little observation to be able to give thanks over again for those incredible ideas you have discussed above. It's really unbelievably generous of you to make publicly all many individuals could possibly have advertised for an electronic book to help with making some bucks for their own end, certainly now that you could have done it if you considered necessary. The principles as well served as the great way to realize that other people online have the same dream just like my personal own to grasp much more in respect of this matter. I am certain there are several more fun situations up front for those who looked at your blog.
yeezy 350 v2
Reply yeezy 500
4:27 PM on December 6, 2022 
I enjoy you because of your own work on this web site. Debby takes pleasure in doing investigation and it's really simple to grasp why. All of us notice all of the dynamic medium you deliver priceless tips through this web site and as well foster response from some other people on that issue and our favorite child is in fact being taught so much. Enjoy the remaining portion of the new year. You're doing a terrific job.
yeezy 500
Reply kd 15
4:50 PM on December 6, 2022 
A lot of thanks for all of your effort on this blog. Kate delights in managing internet research and it's obvious why. All of us hear all relating to the compelling ways you provide invaluable guides through the website and invigorate response from some other people about this subject matter plus my daughter is now studying a lot of things. Enjoy the rest of the new year. You are carrying out a first class job.
kd 15
Reply supreme clothing
8:17 PM on December 6, 2022 
I want to convey my passion for your kindness giving support to people who must have assistance with the concept. Your real commitment to getting the solution all-around ended up being exceptionally advantageous and have constantly empowered workers much like me to reach their targets. This useful help and advice can mean a great deal to me and even further to my office colleagues. Many thanks; from everyone of us.
supreme clothing
Reply off white hoodie
9:06 PM on December 6, 2022 
I truly wanted to post a small word to say thanks to you for some of the fabulous information you are posting on this site. My time intensive internet look up has now been recognized with excellent strategies to exchange with my relatives. I 'd assert that most of us website visitors are undeniably blessed to be in a fine place with so many marvellous people with good advice. I feel very much fortunate to have encountered your webpages and look forward to many more fabulous moments reading here. Thanks once more for a lot of things.
off white hoodie
Reply jordan shoes
9:07 PM on December 6, 2022 
I definitely wanted to post a quick note so as to thank you for all the stunning recommendations you are posting at this site. My time-consuming internet research has at the end been recognized with beneficial ideas to share with my close friends. I would assume that we readers actually are undoubtedly lucky to exist in a fine network with very many perfect individuals with valuable basics. I feel pretty lucky to have seen your entire webpage and look forward to so many more cool minutes reading here. Thank you once again for everything.
jordan shoes
Reply goyard bag
9:08 PM on December 6, 2022 
I'm also writing to make you understand what a perfect discovery my wife's daughter enjoyed reading your webblog. She mastered a good number of issues, including what it is like to possess a wonderful coaching nature to let the others smoothly thoroughly grasp specific tortuous matters. You actually did more than people's expectations. Thanks for churning out the essential, healthy, revealing and in addition unique guidance on this topic to Evelyn.
goyard bag
Reply curry 6
9:51 PM on December 6, 2022 
I not to mention my guys were actually reading through the great recommendations from your site while all of a sudden I got a horrible suspicion I never expressed respect to the site owner for those secrets. Most of the young boys had been as a consequence thrilled to read them and have now honestly been using these things. Thank you for really being considerably considerate and also for figuring out variety of nice useful guides most people are really wanting to discover. Our own honest apologies for not saying thanks to sooner.
curry 6
Reply off white hoodie
10:13 PM on December 6, 2022 
Thanks so much for giving everyone an exceptionally nice opportunity to read from this site. It's always so fantastic plus stuffed with a great time for me and my office friends to search the blog the equivalent of three times in 7 days to read the newest secrets you have got. And lastly, I am actually astounded with the impressive advice served by you. Selected 3 ideas in this post are clearly the most beneficial we have had.
off white hoodie
Reply a bathing ape
2:08 AM on December 7, 2022 
My husband and i got absolutely joyful that Chris managed to round up his investigation from your ideas he came across out of the web page. It is now and again perplexing just to continually be giving away secrets and techniques that many others may have been selling. And we fully grasp we have the website owner to appreciate because of that. All of the explanations you made, the simple site menu, the relationships you help engender - it's many superb, and it's really letting our son and us reason why this article is fun, and that is very mandatory. Thanks for all!
a bathing ape
Reply fear of god
2:46 AM on December 7, 2022 
I am glad for commenting to make you understand what a superb experience my girl found reading your webblog. She came to find numerous issues, not to mention how it is like to have a very effective helping mindset to get other folks completely comprehend various advanced issues. You undoubtedly did more than our expected results. Thank you for presenting such warm and friendly, trusted, edifying as well as easy thoughts on the topic to Evelyn.
fear of god
Reply palm angels t shirt
6:35 AM on December 7, 2022 
I simply wanted to compose a simple message to express gratitude to you for all of the fabulous advice you are showing here. My extensive internet research has at the end been paid with awesome content to talk about with my great friends. I would repeat that we readers actually are truly fortunate to dwell in a fine place with many wonderful professionals with great methods. I feel quite blessed to have come across your web page and look forward to really more pleasurable minutes reading here. Thanks a lot once more for all the details.
palm angels t shirt