Hereditary sensorineural hearing loss of unknown cause involving mitochondrial DNA 1555 mutation.

We report on a family with maternally inherited sensorineural hearing loss, in which no history of aminoglycoside injection and no other specific etiology could be identified in any member. A 1555 A-to-G mutation of mitochondrial DNA was found in all members demonstrating hearing loss. The hearing in the propositus and his sister was severely impaired at a younger age than that in the mother. This case suggests that the 1555 point mutation of mitochondrial DNA has potential to promote inherited nonsyndromic hearing loss without any known etiology. Copyright 2000 S. Karger AG, Basel