Possible Role of Mitochondrial Transfer RNA Gene 5816 A > G Genetic Polymorphism (m.5816A > G) in a 3-Year-Old Child with Dystonia: Report of a Case

Abstract Background Mutations in the mitochondrial transfer RNA (mt-tRNA) gene are a hotspot for DNA (mtDNA) mutations and most common diseases. Methods We identified mt-tRNA 5816 A > G (m.5816 G) mutation 3-year-old child with dystonia who died. performed clinical evaluation, genetic analysis, biochemical investigation function testing. Results Our patient was found to have hyperlactatemia. Electroencephalogram findings were abnormal children numerous multifocal spikes, multispike, spikes slow waves, waves low amplitude fast more pronounced occipital region bilaterally, occurring continuously during sleep. One year later, preexisting had seizures lasting 1 2 hours subsequently mtDNA sequencing revealed that proband, her mother, grandmother all carried m.5816A mutation. Oxygen consumption rate (OCR) assays proband's basal resting OCR, adenosine triphosphate production, proton leak, maximal respiration, spare capacity OCR significantly lower compared healthy of same age. Conclusion The present case demonstrates childhood caused by mutation, which has never been reported before. provide valuable new insights into pathogenic mechanism