Objectives
Connexins (Cxs) are membrane-spannin
g proteins that co-assemble into intercellular
gap
junction channels. Gap
junction channels mediate electrical and biochemical communication between ad
jacent cells and play vital roles as mediators of intercellular molecular si
gnalin
g. Cx-linked deafness hi
ghli
ghts the key role of
gap
junctions in the physiolo
gical processes of hearin
g. Co-localization of Cxs with the
gap
junction system in the inner ear su
ggests a role in cochlear electrolyte homeostasis. Durin
g auditory transduction, they are proposed to maintain membrane potentials by re
gulatin
g the flow of potassium ions between the sensory epithelia of the inner ear.
Methods
Clinical and molecular genetic methods were employed in a Greek proband presenting with bilateral, postlingual, non-syndromic, sensorineural deafness.
Results
We detected a novel c.292C > T (p.R98W) mutation in compound heterozygosity with the c.35delG mutation in the GJB2 gene.
Conclusion
Although mutations in the GJB2 gene usually cause prelingual, severe to profound deafness, compound heterozygosity of the novel c.292C > T (p.R98W) and the c.35delG GJB2 mutations appears to be the cause of postlingual, moderate, sensorineural deafness in our proband.