A novel DFNA5 mutation does not cause hearing loss in an Iranian family.

Abstract

Mutations in DFNA5 lead to autosomal dominant non-syndromic sensorineural hearing loss that starts at the high frequencies. To date, only three DFNA5 mutations have been described, and although different at the genomic DNA level, all lead to exon 8 skipping at the mRNA level. This remarkable fact has led towards the hypothesis that DFNA5-associated hearing loss is caused by a gain-of-function mutation and not by haplo-insufficiency as previously thought. Here, we describe a fourth DFNA5 mutation: the insertion of a cytosine at nucleotide position 640 (AF073308.1:_c.640insC, AAC69324.1:_p. Thr215HisfsX8). Unlike the previously described mutations, this frameshift mutation truncates the protein in exon 5 of the gene. Although the mutation was found in an extended Iranian family with hereditary hearing loss, it does not segregate with the hearing loss phenotype and is even present in persons with normal hearing. This fact provides further support for the hypothesis that DFNA5-associated hearing loss is caused by a gain-of-function mutation.

• Authors: Lut Van Laer, Nicole C Meyer, Mahdi Malekpour, Yasser Riazalhosseini, Mahdi Moghannibashi, Kimia Kahrizi, Ann Vandevelde, Fatemeh Alasti, Hossein Najmabadi, Guy Van Camp, Richard J H Smith
• Journal: Journal of human genetics (J Hum Genet) Vol. 52 Issue 6 Pg. 549-552 ( 2007) ISSN: 1434-5161 [Print] England
• PMID: 17427029 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• GSDME protein, human
• Receptors, Estrogen

Topics

• Cohort Studies
• DNA Mutational Analysis
• Female
• Hearing Loss, Sensorineural (genetics)
• Humans
• Iran
• Male
• Mutation
• Pedigree
• Receptors, Estrogen (genetics)