Investigation of connexin ۲۶ mutations and three large deletions spanning connexin ۳۰ in ۶۳ Iranian families with autosomal recessive non-syndromic hearing loss

Objective: Hearing loss is the most frequent neurosensory defect in human. Mutations in GJB۲ and GJB۶ are responsible for ۵۰% of autosomal recessive non-syndromic hearing loss (ARNSHL) cases. Here we report on the frequencies of GJB۲ and GJB۶ mutations and three large deletions spanning the GJB۶ gene including Del (GJB۶-D۱۳S۱۸۳۰), Del (GJB۶-D۱۳S۱۸۵۴) and a >۹۲۰ kb deletion in patients affected by ARNSHL referred to Kawsar's Human Genetics Research Center. Materials and Methods: In this study, ۹۴ patients from ۶۳ families with ARNSHL were investigated. Patient's homozygote for ۳۵delG were screened and left out of the study and the remaining samples were analyzed by sequencing of GJB۲ and GJB۶ genes. Also the three large deletions spanning the GJB۶ gene were analyzed by Real Time PCR Results: In this study we found GJB۲ mutations in ۱۳ families (۲۰.۶%) out of ۶۳. The ۳۵delG mutation was the most common mutation in the studied population (۶۱.۵%). Other GJB۲ mutations were delE۱۲۰, R۱۲۷H, W۲۴X, and V۳۷I. The heterozygous or negative cases for the GJB۲ mutations were screened for mutation in the GJB۶ gene by sequencing and no mutation was observed. Also, we checked the three large deletions in GJB۶, we found no mutations. Conclusion: Low frequency of mutations in the GJB۲ gene implies that other genes may be involved in causing non-syndromic hearing loss in our country.

کلیدواژه ها:

PCR ، GJB۲ ، PCR ، GJB۲ ، Non Syndromic Hearing Loss ، population ، ناشنوایی غیرنشانگانی ، جمعیت