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Updated: Jan 14, 2026

Modeling Mitochondrial Disease Using Brain Organoids: A Focus on Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like Episodes
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Modeling Mitochondrial Disease Using Brain Organoids: A Focus on Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like Episodes

Published on: October 10, 2025

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Mitochondrial dysfunction in MED13 variant-associated disease: a case of infantile spasms, cardiomyopathy and

Mizuki Harada1,2, Takanori Onuki3, Hiromi Nyuzuki3,4

  • 1Department of Pediatrics, Uonuma Kikan Hospital, Niigata, Japan. mizukiharada7302@gmail.com.

Human Genome Variation
|October 23, 2025
PubMed

Insights

A new MED13 gene variant caused infantile spasms, heart problems, and liver issues in an infant. This case links MED13 variants to systemic mitochondrial dysfunction, revealing a new disease pathway.

Area of Science:

  • Genetics
  • Mitochondrial Biology
  • Pediatric Neurology

Background:

  • MED13 gene variants are rarely associated with human disease.
  • Mitochondrial dysfunction can manifest in various organs, leading to severe symptoms.

Purpose of the Study:

  • To report a novel de novo heterozygous MED13 variant.
  • To investigate the link between this variant and systemic mitochondrial dysfunction in an infant.

Main Methods:

  • Clinical case presentation of an infant with specific symptoms.
  • Autopsy of cardiac and hepatic tissues.
  • Analysis of mitochondrial abnormalities and respiratory chain complex activity.

Main Results:

  • Identification of a de novo heterozygous MED13 variant (c.2503C>T, p.Pro835Ser).
  • Infant presented with infantile spasms, hypertrophic cardiomyopathy, and hepatomegaly.
  • Autopsy confirmed mitochondrial abnormalities and reduced respiratory chain complex activity in cardiac and hepatic tissues.

Conclusions:

  • This is the first report linking a MED13 variant to systemic mitochondrial dysfunction.
  • The findings suggest a novel pathogenic mechanism for MED13-related disorders.

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