Mitochondrial DNA 3252A>G mutation presenting as MERRF/MELAS overlapping syndrome: A case report

Abstract

We report a case of 25 years old male presented with a complex phenotype of myoclonic epilepsy with ragged red fibers (MERRF) and mitochondrial encephalomyopathy, lactic acidosis and stroke- like episodes (MELAS) harbouring m.3252A>G mutation in the mitochondrially encoded tRNA leucine 1 (UUA/G) [MT-TL1] gene encoding the mitochondrial transfer ribonucleic acid (tRNA) for leucine. He presented with frequent myoclonus seizure, stroke-like episodes, elevated blood lactate with muscle biopsy showed numerous ragged-red fibers suggestive of a mitochondrial disorder. Whole mitochondrial genome sequencing revealed no mutations other than the A-to-G transition at nucleotide position 3252. This case report is the first to describe the m.3252A>G mutation in association with the MERRF/MELAS overlap syndrome.