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An autosomal recessive, severe mitochondrial disease with multisystemic manifestations and early onset. Clinical features include delayed psychomotor development, impaired intellectual development with speech delay, mild dysmorphic facial features, hypotonia, ataxia, and seizures. Brain imaging shows bilaterally symmetrical necrotic lesions in subcortical brain regions. Mortality is high, due to episodes of severe metabolic acidosis and coma.




COX deficiency, French Canadian type
COX deficiency, Saguenay-Lac-Saint-Jean type
Cytochrome c oxidase deficiency, French Canadian type
Leigh syndrome, French-Canadian type
Leigh syndrome, Saguenay-Lac-Saint-Jean type


Primary mitochondrial disease


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