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GTR Home > Conditions/Phenotypes > Congenital lactic acidosis, Saguenay-Lac-Saint-Jean type


Mitochondrial complex IV deficiency nuclear type 5 (MC4DN5) is an autosomal recessive severe metabolic multisystemic disorder with onset in infancy. Features include delayed psychomotor development, impaired intellectual development with speech delay, mild dysmorphic facial features, hypotonia, ataxia, and seizures. There is increased serum lactate and episodic hypoglycemia. Some patients may have cardiomyopathy, abnormal breathing, or liver abnormalities, reflecting systemic involvement. Brain imaging shows lesions in the brainstem and basal ganglia, consistent with a diagnosis of Leigh syndrome (see 256000). Affected individuals tend to have episodic metabolic and/or neurologic crises in early childhood, which often lead to early death (summary by Debray et al., 2011). For a discussion of genetic heterogeneity of mitochondrial complex IV (cytochrome c oxidase) deficiency, see 220110. [from OMIM]

Available tests

60 tests are in the database for this condition.

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Genes See tests for all associated and related genes

  • Also known as: CLONE-23970, GP130, LRP130, LSFC, MC4DN5, LRPPRC
    Summary: leucine rich pentatricopeptide repeat containing

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