The purpose of this review is to assess the current literature on deafness nonsyndromic autosomal dominant 2 (DFNA2) hearing loss and the mutations linked to this disorder. Hearing impairment, particularly nonsyndromic hearing loss, affects multiple families across the world. After the identification of the DFNA2 locus on chromosome 1p34, multiple pathogenic mutations in two genes (GJB3 and KCN...

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...

Hearing loss (HL) is an extremely common neurosensory deficit with a heterogeneous etiology including environmental and genetic causes. The incidence of profound sensorineural HL in the United States is 186 per 100,000 births (Morton and Nance 2006). In developed nations, more than 60% of individuals affected with HL have a genetic etiology that can be classified by the mode of inheritance and ...

Autosomal recessive non-syndromic hearing loss is the most common form of inherited childhood deafness. Identification of the responsible gene in this type of hearing loss presents difficulties because of marked genetic heterogenicity and limited clinical presentation. A two-year-old girl was referred to our clinic because of congenital hearing loss. Family history showed that her brother and s...

Dysfunctional gap junctions caused by GJB2 (CX26) and GJB6 (CX30) mutations are implicated in nearly half of nonsyndromic hearing loss cases. A recent study identified a heterozygous mutation, c.119C>T (p.A40V), in the GJB6 gene of patients with nonsyndromic hearing loss. However, the functional role of the mutation in hearing loss remains unclear. In this study, analyses of cell biology indica...

Purpose: The mutation of the SLC26A4 gene is the second most common cause of congenital hearing loss after GJB2 mutations. It has been identified as a major cause of autosomal recessive nonsyndromic hearing loss associated with enlarged vestibular aqueduct and Pendred syndrome. Although most studies of SLC26A4 mutations have dealt with hearing-impaired patients, there are a few reports on the f...

The most common cause of nonsyndromic autosomal recessive hearing loss is mutations in GJB2. The mutation spectrum and prevalence of mutations vary significantly among ethnic groups, and the relationship between p.V37I mutation in GJB2 and the hearing phenotype is controversial. Among the 3,864 patients in this study, 106 (2.74%) had a homozygous p.V37I variation or a compound p.V37I plus other...