despite the enormous heterogeneity of genetic hearing loss, mutations in the gjb2 (connexin 26) gene located on “dfnb1” locus (13q12) account for up to 50% of cases of autosomal recessive non-syndromic hearing loss (arnshl) in some populations. this study describes the analysis of 100 autosomal recessive and sporadic nonsyndromic hearing loss individuals from 79 families each having at least on...

Discriminating between inherited and non-inherited sporadic hearing loss is challenging. Here, we attempted to delineate genetic inheritance in simplex cases of severe-to-profound congenital hearing loss in Korean children. Variations in SLC26A4 and GJB2 in 28 children with bilateral severe-to-profound non-syndromic hearing loss (NSHL) without familial history were analyzed using Sanger sequenc...

introduction: with prevalence figures close to 0.2% at birth, hearing loss (hl) is the most frequent sensory impairment in childhood. in developed countries, genetic causes account for more than 60% of congenital hl, most often resulting in non-syndromic deafness, which is usually autosomal recessive. hereditary nonsyndromic hearing loss (nshl) in iran is highly heterogeneous, rendering molecul...

objective(s) despite the enormous heterogeneity of genetic hearing loss, most non-syndromic hearing losses are caused by mutations in the gjb2 gene. we aimed to characterize the mutation profiles of 100 iranian deaf patients that were under 10 years old. materials and methods patients were tested with direct sequencing of entire coding region of the gjb2 gene. results eight known mutations plus...

Congenital hearing loss with many genetic and environmental causes affects 1 in 1000 newborns. Mutations in the GJB2(Gap Junction Beta-2) gene encoding the gap junction protein connexin 26 have been established as the main cause of autosomal recessive non-syndromic hearing loss. The aim of this study was to study the frequency of one mutation (35delG) of GJB2 gene in Kerman non-syndromic deaf p...

Hereditary hearing loss is divided into two groups, syndromic and non-syndromic, the latter being more common and highly heterogeneous. Linkage analyses were performed on a Japanese family showing a dominant form of non-syndromic progressive sensorineural hearing loss. This gene (DFNA11) was localized within the region of chromosome 11q which contains the second gene for a recessive form of non...

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...

About 120 million people worldwide suffer from congenital (early-onset) hearing loss. Thirty percent of them have syndromic hearing loss and the remaining 70% have non-syndromic hearing loss. In addition, a large number of elderly people worldwide suffer from age-related (late-onset) hearing loss. c-Ret and c-RET have been shown to be essential for the development and maintenance of neurons inc...

Objective(s) Despite the enormous heterogeneity of genetic hearing loss, most non-syndromic hearing losses are caused by mutations in the GJB2 gene. We aimed to characterize the mutation profiles of 100 Iranian deaf patients that were under 10 years old. Materials and Methods Patients were tested with direct sequencing of entire coding region of the GJB2 gene. Results Eight known mutations...

Over the last decade, a number of distinct mutations in the mtDNA (mitochondrial DNA) have been found to be associated with both syndromic and non-syndromic forms of hearing impairment. Their real incidence as a cause of deafness is poorly understood and generally underestimated. Among the known mtDNA mutations, the A1555G mutation in the 12S gene has been identified to be one of the most commo...