Medical Genetics (5) Respiratory chain mtDNA mutations Intergenomic communication Multiple mtdna deletions mtDNA depletion Nuclear gene defects Tissue-specific Generalized Succinic dehydrogenaseMedical Genetics (5) Respiratory chain mtDNA mutations Intergenomic communication Multiple mtDNA deletions mtDNA depletion Nuclear gene defects Tissue-specific Generalized Succinic dehydrogenase