Prevalence of GJB2 Mutations in Affected Individuals from United Arab Emirates with Autosomal Recessive Nonsyndromic Hearing Loss.

Abstract

Mutations in the gap junction protein beta 2 (GJB2) gene are responsible for more cases of nonsyndromic recessive hearing loss than any other gene. The purpose of our study was to evaluate the prevalence of GJB2 mutations among affected individuals from United Arab Emirates (UAE). There were 50 individuals diagnosed with hereditary hearing loss and 120 healthy individuals enrolled in the study. The Sanger sequencing method was used to screen the GJB2 coding region in all affected individuals. The c.-1G>A variant was determined by the polymerase chain reaction-restriction fragment length polymorphism method in normal individuals. Nine cases with bi-allelic mutations and three cases with mono-allelic mutations were detected in 12 out of 50 patients (24%). The homozygous mutation c.35delG was identified as the cause of hearing loss in six participants (12%). The mutation c.506G>A was identified in three affected individuals (6%). The allelic frequency (14%) and low percentage of individuals that were homozygous (2%) for the c.35delG mutation suggest that there are other genes responsible for nonsyndromic deafness in the UAE population. The results reported here are a preliminary step in collecting epidemiological data regarding autosomal recessive nonsyndromic hearing loss related to GJB2 gene mutations among the UAE population. The c.35delG mutation of the GJB2 gene is the most frequently seen causative mutation in the UAE and is followed by the p.Cys169Tyr mutation.