BACKGROUND & OBJECTIVES Hearing impairment is a common and heterogeneous sensory disorder in humans. Among about 90 genes, which are known to be associated with hearing impairment, mutations in the GJB2 (gap junction protein beta 2) gene are the most prevalent in individuals with hereditary hearing loss. Contribution of the other deafness-causing genes is relatively poorly understood. Here, we ...

The frequency of inherited bilateral autosomal recessive non-syndromic hearing loss (ARNSHL) in Pakistan is 1.6/1000 individuals. More than 50% of the families carry mutations in GJB2 while mutations in MYO15A account for about 5% of recessive deafness. In the present study a cohort of 30 ARNSHL families was initially screened for mutations in GJB2 and MYO15A. Homozygosity mapping was performed...

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...

Genetic causes account for more than half of congenital hearing loss cases. The most frequent mutations found in non-syndromic hearing loss patients occur in GJB2 and SLC26A4. Mitochondrial genome mutations are also prevalent. However, the frequency of common hearing loss mutations in the Chinese population has not yet been well estimated. Here, we implemented the SNaPshot genotyping method to ...

Age-Related Hearing Impairment (ARHI) is one of the frequent sensory disorders registered in 50% of individuals over 80 years. ARHI is a multifactorial disorder due to environmental and poor-known genetic components. In this study, we present the data on age-related hearing impairment of 48 heterozygous carriers of mutation IVS1+1G>A (GJB2 gene) and 97 subjects with GJB2 genotype wt/wt in the R...

Purpose of this study was to molecularly characterize a family in which two brothers (46 and 36 years) presented with a combination of retinitis pigmentosa (RP) and severe sensorineural hearing loss while father and sister (71 and 41 years) presented with isolated RP. Retinal phenotype was compared with phenotype of 17 patients with Usher syndrome type 1. Ophthalmological examination included a...

Fifty to eighty percent of autosomal recessive congenital severe to profound hearing impairment result from mutations in a single gene, GJB2, that encodes the protein connexin 26. One mutation of this gene, the 35delG allele, is particularly common in white populations. We report evidence that the high frequency of this allelic variant is the result of a founder effect rather than a mutational ...