Iolated late-onet cone-rod dytrophy revealing a familial neurogenic mucle weakne, ataxia, and retiniti pigmentoa yndrome with the T8993G mitochondrial mutation

PURPOE: To report a late-onet cone-rod dytrophy that revealed a familial neurogenic mucle weakne, ataxia, and retiniti pigmentoa yndrome a a conequence of the T8993G mitochondrial mutation. METHOD: Obervational cae erie. A 42-year-old female dicloed a late-onet retinal dytrophy. The family hitory revealed that her three on, one of them deceaed at the age of 4, had mental and neurologic impairment of variable everity. The retinal dytrophy of the mother wa claified a a cone-rod dytrophy. Retinal dytrophy wa ubequently diagnoed in the two urviving on. creening for mutation in the mitochondrial DNA (mtDNA) wa performed becaue of the combination of neurologic involvement and retinal dytrophy in thi family. REULT: Molecular analyi of the mtDNA revealed the ATPae-6 gene T8993G mutation in the mother and the two on. CONCLUION: Thi family illutrate the remarkably variable expreion of retinal and ytemic manifetation related to the T8993G mutation ranging from an iolated late-onet cone-rod dytrophy to a evere neurodegenerative proce with a dramatic outcome. Genetic couneling for retinal dytrophie require careful evaluation of the familial medical hitory.