Connexin 26

Back in March, Isaac had blood samples taken for the recommended genetic testing. This month we found out the results. He tested positive for the most common form of genetic based hearing loss, Connexin 26. This has cleared up some of the question mark areas we've been worried/wondering about but has also surprised Travis and I. We had NO IDEA either of us were carriers and now to find out that we each had a part in Isaac's hearing loss has been a bit of bad news but I guess more information, good or bad, will help us understand this disability better. Here are some snippets of information of my research on this. (I probably should have included the source references but since this isn't a formal research paper, please don't grade it as such :-)
Children born with bilateral (both ears) severe to profound sensorineural hearing losses are typically referred for genetic testing for Connexin 26 mutations. Connexin 26 mutations are genetically transmitted from parent to child in a recessive manner, which means that an affected individual must inherit one copy of the non-functioning gene from each parent. Carriers who only have one copy of the gene (i.e. one normal gene and one mutated gene) do not manifest any of the signs of the condition, but have a 1 in 2 chance of passing on the defective gene to their children (who would then also be carriers only), and a 1 in 4 chance of having an affected child if the other parent is also a carrier. Connexin 26 mutations produce a pre-lingual hearing loss, because it affects the child before they are old enough to develop speech.

Usually, mutations in the Connexin 26 gene are recessive, meaning that both the mother and the father of the baby need to have the mutation for it to cause a hearing loss in the baby. Hearing loss due to mutations of the Connexin 26 gene is almost always congenital, severe to profound, not progressive, and occurs without any other medical problems (nonsyndromic), meaning the mutation produces only isolated hearing loss. There is NO increased risk for other medical problems that are commonly associated with hearing loss such as blindness, thyroid problems, kidney problems, or balance disorders. However, there is in a minority of cases a higher incidence of skin disorders in patients with a Connexin 26 mutation.