To date, 135 loci and 50 genes have been identified as causes of nonsyndromic hearing loss. Until recently, four loci (DFN2, DFN3, DFN4, and DFN6) had been implicated in nonsyndromic X-linked hearing loss; however, a new classification (DFNX1-5) has been proposed to reduce confusion in the terminology. The different types of nonsyndromic X-linked hearing loss demonstrate various clinical featur...

OBJECTIVE To study connexin 26 (Cx26) gene mutations among autosomal recessive non-syndromal hearing loss in Kuwaiti patients and evaluate their effect on phenotypes. SUBJECTS AND METHODS This cross sectional study included 100 patients aged between 6 months and 18 years, who were referred to the Sheikh Salem Al-Ali Centre for audiology and speech evaluation of autosomal recessive non-syndrom...

The GJB2 gene is located on chromosome 13q12 and it encodes the connexin 26, a transmembrane protein involved in cell-cell attachment of almost all tissues. GJB2 mutations cause autosomal recessive (DFNB1) and sometimes dominant (DFNA3) non-syndromic sensorineural hearing loss. Moreover, it has been demonstrated that connexins are involved in regulation of growth and differentiation of epidermi...

Abstract Background Previous studies have revealed that mutations of Spalt Like Transcription Factor 1 ( SALL1 ) are responsible for Townes-Brocks syndrome (TBS), a rare genetic disorder is characterized by an imperforate anus, dysplastic ears, thumb malformations and other abnormalities, such as hearing loss, foot malformations, renal impairment with or without genitourinary congenital heart d...

The TECTA gene, which encodes alpha-tectorin, is known as a causative gene for DFNA8/DFNA12, and DFNB21 hearing loss in humans. In the present study, mutation analysis of the TECTA gene was performed in 62 Korean patients with hereditary hearing loss. Two novel nucleotide substitutions, p.V317E and p.T1866M, were identified for the first time in the Korean population. These mutations result in ...

Hereditary deafness has proved to be extremely heterogeneous genetically with more than 40 genes mapped or cloned for non-syndromic dominant deafness and 30 for autosomal recessive non-syndromic deafness. In spite of significant advances in the understanding of the molecular basis of hearing loss, identifying the precise genetic cause in an individual remains difficult. Consequently, it is impo...