A new compound heterozygous mutation in GJB2 causes nonsyndromic hearing loss in a consanguineous Iranian family

Abstract

Objective: To investigate mutations in GJB2 in a consanguineous Iranian family with multiple members affected by non-syndromic hearing loss.

Methods: DNA was extracted from blood samples and the coding region of the conexin 26 gene was amplified using PCR. Bidirectional sequencing was carried out on PCR products.

Results: Direct sequencing of the PCR products led to the identification of a novel compound heterozygous mutation of c.551G>C/c.397T>G (p.R184P/p.W133G) and a previously reported homozygous mutation c.551G>C (R184P/R184P). Compound heterozygous mutation was identified in the father and his daughter and homozygous mutation was identified in his affected son. In silico analysis of p.W133G predicted mutation has deleterious effect on protein structure.

Conclusion: These results show the usefulness of GJB2 mutation screening and bioinformatic analysis for genetic diagnosis and counseling of non-syndromic hearing loss.

Keywords: Compound heterozygous mutation; Connexin 26; GJB2 gene; Non-syndromic hearing loss.