[Application of next generation sequencing and Sanger sequencing in a pedigree affected with hereditary non-syndromic...

To detect potential mutation in a pedigree affected with autosomal recessive non-syndromic deafness.

Mutation analysis was carried out by next generation sequencing, and suspected mutations were verified by Sanger sequencing.

A heterozygous c.235delC mutation of the GJB2 gene, together with compound heterozygous mutations of the OTOF gene [c.1194T>A (p.D398E) and c.2180A>G (p.N727S)] were detected in the proband. The sister of the proband (also had hearing loss) has carried a heterozygous c.235delC mutation in the GJB2 gene, in addition with a heterozygous c.2180A>G(p.N727S) mutation of the OTOF gene. By Sanger sequencing, a heterozygous IVS1+2T>A mutation was further detected in the non-coding region of the GJB2 gene in both sisters.

The compound heterozygous c.235delC and IVS1+2T>A mutations of the GJB2 gene probably account for the hearing loss in the two sisters, among which IVS1+2T>A is considered as a novel pathogenic mutation of the GJB2 gene.