Published: 2020-04-21

Prevalence of congenital non syndromic hearing loss among offspring of consanguineous marriage: a pilot study

Gangadhar K. S., Geetha Bhaktha, Manjula B., Nageshwari P.


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.


Hearing impairment, GJB2 mutation, W24X gene, RFLP

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