Mapping of New Locus in Deafness

Abstract

Previous studies have reported that Pendred Syndrome (PDS) contributes approximately 4.7-7.2% of recessive hereditary deafness in Pakistani population. More than 367 mutations of SLC26A4 have been reported so far with PDS. Identification of recurrent mutations reveals widespread lineage diversity and mutational specificity of a population. This study reports p.Y556C mutation as a recurring mutation in Punjabi population of Pakistan. A detailed genetic evaluation of four unrelated but ethnically similar families from Punjab province was performed. Linkage to SLC26A4 locus was confirmed through linkage analysis using Short Tandem Repeat Markers (D7S2420, D7S2459 and D7S2456). p.Y556C was identified as causative mutation by Sanger Sequencing. A known missense mutation p.Y556C in exon 15 of SLC26A4 gene was identified in all the four families. It may be concluded that p.Y556C mutation is a recurrent mutation in Punjab province of Pakistan.