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GTR Home > Conditions/Phenotypes > Holocarboxylase synthetase deficiency

Holocarboxylase synthetase deficiency

Synonyms
MULTIPLE CARBOXYLASE DEFICIENCY, EARLY ONSET
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Holocarboxylase synthetase deficiency, a biotin-responsive multiple carboxylase deficiency (MCD), is characterized by metabolic acidosis, lethargy, hypotonia, convulsions, and dermatitis. Most patients present in the newborn or early infantile period, but some become symptomatic in the later infantile period (summary by Suzuki et al., 2005). Also see biotinidase deficiency (253260), another form of MCD with a later onset. Care must be taken to differentiate the inherited multiple carboxylase deficiencies from acquired biotin deficiencies, such as those that develop after excessive dietary intake of avidin, an egg-white glycoprotein that binds specifically and essentially irreversibly to biotin (Sweetman et al., 1981) or prolonged parenteral alimentation without supplemental biotin (Mock et al., 1981). [from OMIM]

Available tests

77 tests are in the database for this condition.

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Clinical tests (77 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: HCS, HLCS
    Summary: holocarboxylase synthetase

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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Reviews

Clinical resources

Practice guidelines

  • ACMG ACT, 2022
    American College of Medical Genetics and Genomics, Newborn Screening ACT Sheet, Elevated C5-OH Acylcarnitine, Organic Acidemias, 2022
  • ACMG Algorithm, 2022
    American College of Medical Genetics and Genomics, Algorithm, Organic Acidemias: Elevated C5-OH, 2022

Molecular resources

Consumer resources

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