Mitochondrial complex I deficiency caused by a deleterious NDUFA11 mutation.
Itai Berger1, Eli Hershkovitz, Avraham Shaag
1Pediatric Neurology Unit, Hadassah-Hebrew University Medical Center, Jerusalem.
Annals of Neurology
|February 29, 2008
Summary
A genetic mutation in the NDUFA11 gene causes complex I deficiency, a common respiratory chain disorder. This finding is crucial for diagnosing infantile lactic acidemia and encephalocardiomyopathy.
Area of Science:
- Biochemistry
- Genetics
- Molecular Biology
Background:
- Complex I deficiency is the most frequent defect of the respiratory chain.
- Clinical manifestations include neonatal lactic acidosis, Leigh's disease, and multi-organ disorders.
Observation:
- A splice-site mutation in the NDUFA11 gene was identified in six patients from three families.
- Patients presented with encephalocardiomyopathy or fatal infantile lactic acidemia.
Findings:
- The NDUFA11 mutation is predicted to destabilize the complex I enzyme by abolishing its first transmembrane domain.
- This genetic defect provides a molecular basis for the observed clinical phenotypes.
Implications:
- NDUFA11 mutation analysis is recommended for diagnosing isolated complex I deficiency.
- This research aids in understanding the genetic underpinnings of mitochondrial disorders.
- Early diagnosis can potentially guide therapeutic strategies for affected infants.
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