A novel mutation in the mitochondrial tRNASer(UCN) gene in a family with non-syndromic sensorineural hearing impairment
- Tim P Hutchina,
- Mick J Parkerb,c,
- Ian D Youngc,
- Adrian C Davisb,
- Louise J Pulleyna,
- Jayne Deeblea,
- Nicholas J Lencha,
- Alex F Markhama,
- Robert F Muellerd
- aMolecular Medicine Unit, St James's University Hospital, Leeds LS9 7TF, UK, bMRC Institute of Hearing Research, University Park, Nottingham NG7 2RD, UK, cDepartment of Clinical Genetics, City Hospital, Nottingham NG5 1PB, UK, dDepartment of Clinical Genetics, St James's University Hospital, Leeds LS9 7TF, UK
- Dr Hutchin, Molecular Medicine Unit, Clinical Sciences Building, St James's University Hospital, Beckett Street, Leeds LS9 7TF, UK,t.p.hutchin{at}leeds.ac.uk
- Revised 22 March 2000
- Accepted 10 April 2000
Abstract
We describe a family with non-syndromic sensorineural hearing impairment inherited in a manner consistent with maternal transmission. Affected members were found to have a novel heteroplasmic mtDNA mutation, T7510C, in the tRNASer(UCN) gene. This mutation was not found in 661 controls, is well conserved between species, and disrupts base pairing in the acceptor stem of the tRNA, making it the probable cause of hearing impairment in this family. Sequencing of the other mitochondrial tRNA genes did not show any other pathogenic mutations. Four other mutations causing hearing impairment have been reported in the tRNASer(UCN) gene, two having been shown to affect tRNASer(UCN) levels. With increasing numbers of reports of mtDNA mutations causing hearing impairment, screening for such mutations should be considered in all cases unless mitochondrial inheritance can be excluded for certain.
