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Mitochondrial DNA 3243A>T mutation in a patient with MELAS syndrome

Takahiro Ikeda1, Hitoshi Osaka1, Hiroko Shimbo2

  • 11Division of Pediatrics, Jichi Medical University, Shimotsuke, Tochigi Japan.

Human Genome Variation
|September 14, 2018
PubMed

Insights

A rare mitochondrial mutation, m.3243A>T, was identified in a patient with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). This finding supports m.3243A>T as a cause of the MELAS phenotype.

Area of Science:

  • Genetics
  • Neurology
  • Mitochondrial Diseases

Background:

  • Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a common mitochondrial disorder.
  • The m.3243A>G mutation in the MTTL1 gene is found in approximately 80% of MELAS cases.

Observation:

  • A case of MELAS was identified with a rare heteroplasmic m.3243A>T mutation.
  • This mutation was detected through direct sequencing of the MTTL1 gene.

Findings:

  • The m.3243A>T mutation, previously reported in a limited number of cases, is confirmed to be associated with the MELAS phenotype.
  • This specific mutation can lead to the development of MELAS.

Implications:

  • This case broadens the spectrum of known genetic mutations causing MELAS.
  • Further research into rare MTTL1 mutations is warranted for improved diagnosis and understanding of MELAS pathogenesis.

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