A Novel Mutation in the GJB2 (Connexin 26) Gene in Egyptian Children with Non-syndromic Sensorineural Hearing Loss

Abstract

This study aimed to investigate the frequency of any novel gene mutations, in human GJB2 gene among Egyptians with familial sensorineural non-syndromic hearing impairment. PCR amplifying the entire coding region of GJB2 gene and direct DNA sequencing to analyze mutations in this gene among 78 cases with autosomal recessive congenital non syndromic hearing loss was used. We describe for the first time a novel mutation in the coding region of the GJB2 gene. A deletion mutation of T at position 59, in the intracellular domain of connexin 26, resulting in a frameshift at the 20 th amino acid leading to a premature termination of the protein was detected in 9% of the studied cases. These data provide a novel molecular explanation for the role of GJB2 mutation in hearing loss to be taken into consideration in the genetic diagnosis and counseling of non-syndromic sensorineural hearing loss in Egyptians.