LT Leung, MMK Lee, SSW Cheng, HM Luk, IFM Lo

Abstract

Mitochondrial m.1555A>G mutation in the 12S rRNA gene (MIM* 561000) is associated with maternally-inherited aminoglycoside–induced hearing loss and non–syndromic deafness. Herein we report 14 Hong Kong Chinese families with m.1555A>G mutation. Individuals in hese families had variable hearing thresholds ranging from normal to profound hearing impairment with variable age of onset, which were consistent with typical findings of incomplete penetrance and variable expressivity for m.1555A>G mutation in previous studies overseas and among the Chinese population. No patient could recall previous history of exposure to aminoglycoside or antibiotic before onset of hearing impairment. It is hoped that through this study, the awareness of m.1555A>G mutation related hearing impairment could be raised among healthcare professionals and the general public so that carriers' exposure to potentially ototoxic drugs could be avoided.