Schoeman, Elizna M, Van Der Westhuizen, Francois H, Erasmus, Elardus et al. · BMC medical genetics · 2017 · DOI
This study examined the DNA inside the energy-producing parts of cells (mitochondria) in 93 ME/CFS patients from the UK and South Africa. The researchers looked for specific mutations that are known to cause mitochondrial disease. They found that these known harmful mutations were not present in the ME/CFS patients studied, suggesting that ME/CFS is not caused by these well-established mitochondrial mutations.
This study addresses an important question about whether ME/CFS might be caused by mitochondrial DNA defects—a hypothesis that had gained attention given the prevalence of fatigue in mitochondrial disease. The findings clarify that while mitochondrial dysfunction may play a role in ME/CFS, the known genetic mutations that cause primary mitochondrial disease are not present in ME/CFS patients, helping distinguish these conditions.
This study does not prove that mitochondria are not involved in ME/CFS—only that known, pathogenic mtDNA mutations are not common. It does not examine nuclear genes involved in mitochondrial function or common DNA variations that might increase susceptibility. The negative findings do not explain what actually causes ME/CFS or rule out mitochondrial dysfunction from other genetic or acquired causes.