Scientists at Kobe University in Japan recently carried out research on 1,120 Japanese patients who were suffering from idiopathic sensorineural hearing loss, and “discovered a novel mutation in the genetic make-up of DIA1 molecule (DIAPH1), which is involved in the lengthening of linear actin filaments,” according to Science Daily.
Researchers claim DFNA1 is the causative gene for autosomal dominant nonsyndromic sensorineural deafness.
Sensorineural hearing loss (SNHL) is one of three types of hearing loss, and essentially refers to hearing loss caused by damage of the inner ear.
Sensorineural hearing loss is one of the most common. I myself, Stu Nunnery, and many of the Hearing Like Me authors have sensorineural hearing loss. For me, it happened suddenly in my left ear, but others are born with it. According to the Centre for Communication and Communication, “hearing loss occurs in 5 out of every 1,000 newly born infants [in the USA].”
Currently, there is no cure for sensorineural hearing loss. However, many sufferers benefit from the use of hearing aids. (I don’t know where I’d be without mine!)
Around a hundred genes have been identified as having causal links to sensorineural hearing loss. However, as Science Daily explains, “there are many unexplained aspects to the process, such as the type of mutation occurring in these genes, and how this causes hearing impairment. DFNA1 was first suggested as a causative gene for this in 1997, but doubts were cast regarding its universality and properties.” (‘Nonsyndromic’ means ‘not associated with other signs and symptoms’.)
Of the causative genes associated with sensorineural hearing loss, around one-third are genes that encode proteins with functions related to the protein, ‘actin.’
“In two families they discovered a novel mutation in the genetic make-up of DIA1 molecule (DIAPH1), which is involved in the lengthening of linear actin filaments. These filaments play an important function in the formation and maintenance of auditory hair and inner ear hair cells. The researchers used biochemical and biological analysis methods on a molecular level to prove that the DIA1 mutant protein created by the mutation is an active form variant that lengthens actin filaments even without external stimulation.”
Additionally, researchers were able to genetically modify a mouse that manifested the DIA1 mutant protein. After studying the mouse, they said it, “demonstrated progressive deafness, starting in the upper registers when young, and advancing with age until it covered all registers.”
Genetically modified mice will be used to find the compounds that transform actin functions within the inner ear hair cells.
Scientists hope that this could potentially lead to the development of treatment for hereditary DFNA1 and other forms of hereditary sensorineural hearing loss.
They suggest that perhaps in future, this could also be the key to discovering a treatment for acquired sensorineural hearing loss.