Prevalence of congenital non syndromic hearing loss among offspring of consanguineous marriage: a pilot study
Keywords:Hearing impairment, GJB2 mutation, W24X gene, RFLP
Background: Mutations in the gene encoding the gap-junction protein connexin-26, is understood to be the most important cause of non-syndromic hearing loss (NSHL). An attempt to identify the single nucleotide polymorphism (SNP) for W24X mutation was done. Consanguineous marriage was seen among the NSHL subjects.
Methods: SNP was identified using restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). Forty-five subjects were screened for congenital hearing loss. Twenty subjects matched the inclusion criteria and were included in the study.
Results: 5 out of 20 subjects were found to have mutation i.e., 25%. Though consanguinity is known to cause autosomal recessive defect, the same could not be depicted in this study.
Conclusions: 25% of the study population had a mutation in their gene and the rest though had consanguineous marriage had not been affected genotypically.
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