Clinical Course of Hearing and Language Development in <i>GJB2</i> and Non-<i>GJB2 </i>Deafness following Habilitation with Hearing Aids

Abstract

Mutations in the GJB2 gene (connexin 26) are the most common cause of nonsyndromic autosomal recessive sensorineural hearing loss. Genetic testing of GJB2 may offer opportunities to predict the features of hearing loss and prognostication of speech-language development in children with hearing loss. The present study assessed the clinical features of hearing and some aspects of language development in congenital deafness due either to GJB2 mutations or to other factors in Japanese patients who had been habilitated with hearing aids. Thirty-five unrelated subjects with nonsyndromic, congenital, bilateral sensorineural hearing loss were enrolled in the study. Among them, 16 had biallelic GJB2 mutations related to hearing loss and 17 lacked such mutations. As has been reported in populations of European ancestry, the present Japanese subjects with GJB2 mutations had a relatively high incidence of the flat pattern audiogram and nonprogressive pure tone thresholds compared with subjects without GJB2 mutations. Subjects with GJB2 mutations and those without GJB2 mutations both showed a similar tendency in speech perception, some aspects of language development, and communication methods. In both groups, development of reading ability tended to be normal, but vocabulary development tended to be delayed. The present results establish the basis for future studies to aid in the evaluation and follow-up of patients with congenital hearing loss associated with GJB2 mutations who are habilitated with hearing aids.

Effect of GJB2 235delC and 30-35delG genetic polymorphisms on risk of congenital deafness in a Chinese population

“…Mutations within the GJB2 coding region can cause frameshifts affecting protein translation, influencing gap junction protein structure, and resulting in connexin defects (Mesolella et al, 2004;Matsunaga et al, 2006;Blanchard et al, 2012). Moreover, such polymorphisms may also affect the opening and closing of these channels, blocking or disrupting intercellular exchange.…”

Associação entre fenótipo, desempenho com próteses auditivas e genótipo da deficiência auditiva infantil em crianças com e sem alteração genética

“…Some authors studied the relationship among the use of auditory aids (performance and benefit), language development and speech perception with different manifestations of HI with genetic origin (4)(5)(6) . The results of the three mentioned studies converge to a similar finding, that the genetic mutations do not determine directly the benefit with sound amplification.…”

“…Some studies aim at clarifying the relationship between the use of hearing aids (performance and benefit), language development and speech perception and the different manifestations of hereditary hearing impairments (4)(5)(6) . Other authors (7)(8)(9)(10) studied the performance of subjects with cochlear implantation, according to their hearing impairments, observing that children with genetic alterations present more benefits with cochlear implantation.…”

Value of Genetic Testing in the Otological Approach for Sensorineural Hearing Loss

“…This provides valuable information in making adequate planning of clinical follow-up, estimation of hearing levels for fitting hearing aids, and selection of occupation by patients. 17 Third, prevention of deafness can be done by avoiding use of specific drugs or specific activities in genetically susceptible patients. As an example, patients with A1555G mitochondrial DNA mutation should avoid aminoglycosides which induce or aggravate SNHL by even one injection in subjects with this mutation.…”