Detection of Connexion 26 GENE (GJB2) Mutations in Cases of Congenital Non Syndromic Deafness
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Hearing loss is most common form of genetic hearing disorder. Non-syndromic sensory neural autosomal recessive deafness (NSRD) is the most common form of genetic hearing loss. Mutations in GJB2 gene, which encodes the connexin 26 protein, are major cause of NSRD. The aim of this study is directed towards the mutations caused along the connexin 26 gene using blood samples from nonsyndromic deaf children. The study was conducted on 36 congenitally hearing impaired children who visited to our department with complains of hearing loss and reduced speech and whose age was <10 years with no other congenital anomaly. After a thorough history, clinical examination and all audiological and radiological assessment, blood samples are collected and DNA extraction, PCR and sequencing were done for further genetic analysis. Annotated and documented autosomal recessive (pathogenic) mutations were observed in 57 % of NSRD cases. The frequency of pathogenic mutation was commonest for Ins G between nucleotide 30–35 (40 % of cases) followed by Del T at nucleotide 59(20 % of cases).These two common mutations (singly or doubly) were present in 51.4 % of cases. Present study helps to screen the families with hearing impaired children, which will facilitate the development of strategies for diagnosis and treatment of these common genetic disorders.
KeywordsDeafness Genetic Connexin nonsyndromic
Compliance with ethical standards
Conflict of interest
Author A- Dr. Hansa Banjara, Author B- Dr. Varsha Mungutwar, Author C- Dr. Neha Swarnkar and Author D- Dr. Pradeep Patra declare that they have no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standard of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all parents/legal guardians of children included in the study.
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