A double mutation (G11778A and G12192A) in mitochondrial DNA associated with Leber's hereditary optic neuropathy and cardiomyopathy.

We report a male patient with Leber's hereditary optic neuropathy (LHON) and hypertrophic cardiomyopathy. Besides a G11778A mutation in the ND4 gene of the mitochondrial DNA (mtDNA), one of the most common mutations in LHON patients, sequencing of total mtDNA revealed a G12192A mutation in the tRNA (His) gene that was recently noted to be a risk factor for cardiomyopathy. Because no case of LHON presenting with cardiomyopathy has been reported, the present finding suggests that the G12192A mutation caused cardiomyopathy as an additional symptom. In the present case, the double pathogenic mtDNA mutations may be associated either synergistically or concomitantly with two different clinical manifestations.