A de novo mutation in the adenosine triphosphatase (ATPase) 8 gene in a patient with mitochondrial disorder

Emna Mkaouar-Rebai1, Fatma Kammoun, Imen Chamkha

  • 1Laboratoire de Génétique Moléculaire Humaine, Faculté de Médecine de Sfax, Tunisia. emna_mkaouar@mail2world.com

Insights

A novel mitochondrial DNA mutation, m.8411A>G, is strongly linked to a patient

Area of Science:

  • Genetics
  • Neurology
  • Mitochondrial Biology

Background:

  • Mitochondrial DNA (mtDNA) defects cause diverse human diseases with varied clinical presentations.
  • Understanding the genetic basis of these disorders is crucial for diagnosis and treatment.

Observation:

  • A patient presented with severe psychomotor delay, seizures, leukodystrophy, congenital deafness, tetraplegia, central blindness, and swallowing difficulties.
  • Brain MRI revealed white matter abnormalities, cerebellar atrophy, and involvement of specific brainstem nuclei.

Findings:

  • Whole mitochondrial genome screening identified 19 known polymorphisms and a novel heteroplasmic mutation (m.8411A>G) in the ATPase 8 gene.
  • This de novo mutation, present at 97% heteroplasmy, was absent in 120 controls.

Implications:

  • The m.8411A>G mutation is a potential cause of the patient's complex neurological and developmental phenotype.
  • This finding expands the spectrum of known mtDNA-related disorders and highlights the importance of comprehensive genetic screening.

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