hearing loss (hl) is the most common communication disorder affecting about 1/1000 births worldwide caused by environmental or genetic factors. about 30-50% is attributed to genetic factors and till now more than 85 genes have been implicated in non-syndromic hl. in iran, hl is second to intellectual disability as the most common disability, affecting 1 of every 166 persons. about 15 years ago ...

while hearing loss has been considered to be a very heterogeneous disorder, mutations in gap junction beta 2 (gjb2) gene encoding connexin 26 (cx26) protein are the major cause of autosomal recessive and sporadic non-syndromic deafness in many populations. in this study, we have investigated the prevalence of the gjb2 gene mutations using nested pcr pre screening strategy and direct sequencing ...

Sensorineural non-syndromic hearing loss is the most common disorder which affects 1 in 500 newborns. Hearing loss is an extremely heterogeneous defect with more than 100 loci identified to date. According to the studies, mutations in GJB2 are estimated to be involved in 50- 80% of autosomal recessive non-syndromic hearing loss cases, but contribution of other loci in this disorder is yet ambig...

Dominant GJB2 mutations are known to cause a syndromic form of sensorineural hearing loss associated with palmo-plantar skin manifestations. We present the genotype/phenotype correlations of a new GJB2 mutation identified in three generations of an Italian family (proband, mother and grandfather) whose members are affected by sensorineural hearing impairment associated with adult-onset palmopla...

Using the Hereditary Hearing Loss arrayed primer extension (APEX) array, which contains 198 mutations across 8 hearing loss-associated genes (GJB2, GJB6, GJB3, GJA1, SLC26A4, SLC26A5, 12S-rRNA, and tRNA Ser), we compared the frequency of sequence variants in 94 individuals with early presbycusis to 50 unaffected controls and aimed to identify possible genetic contributors. This cross-sectional ...

Non-syndromic hearing loss (NSHL) is a major public health issue and affects a substantial proportion of newborns worldwide. Currently little information is available about the molecular etiology of hearing impairment in the Chinese population. Therefore, this study aimed to perform a comprehensive investigation on the genetic mutation patterns of non-syndromic deafness in Zhongshan City, a cit...

We report two heterozygous carriers of c.464A>G variation in the GJB2 gene in a Chinese pedigree. The proband with hearing loss most likely inherited the c.464A>G variation from his mother who also carries heterozygous c.79G>A variation and has normal hearing. The pathological significance of c.464A>G variation remains to be determined.

Neuroectodermal syndromes involving the skin and inner ear may be associated with mutations in connexin proteins, which form gap junctions important for intercellular communication. Vohwinkel syndrome (keratodermia mutilans with hearing loss) and keratitis-ichthyosis-deafness (KID) syndrome are rare ectodermal dysplasias associated with dominant mutations in the GJB2 gene encoding connexin 26. ...

The unparalleled heterogeneity in genetic causes of hearing loss along with remarkable differences in prevalence of causative variants among ethnic groups makes single gene tests technically inefficient. Although hundreds of genes have been reported to be associated with nonsyndromic hearing loss (NSHL), GJB2, GJB6, SLC26A4, and mitochondrial (mt) MT-RNR1 and MTTS are the major contributors. In...