[Molecular etiology of non-syndromic hearing impairment in a Chinese family].

ABSTRACT

OBJECTIVE: To investigate the molecular etiology of non-syndromic hearing impairment in two patients in a maternal inherited deafness Chinese family. METHODS: Peripheral blood specimens were collected and DNA templates extracted. The complete mitochondrial genomes and GJB2 gene were sequenced in an ABI 3100 Avant sequencer. RESULTS: The proband (III-5) and her elder sister (III-1) were found to carry the mtDNA 12SrRNA C1494T mutation. The GJB2 gene showed no mutations. The proband had the history of using aminoglycosides before hearing loss, and exhibited severe sensorineural hearing impairment; the proband's sister had no history of using aminoglycosides, and showed moderate sensorineural hearing impairment. CONCLUSION: The molecular etiology of each individual patient in a family yaries with individual genetic background.