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GTR Home > Conditions/Phenotypes > GTP cyclohydrolase I deficiency with hyperphenylalaninemia

GTP cyclohydrolase I deficiency with hyperphenylalaninemia

Synonyms
HYPERPHENYLALANINEMIA, TETRAHYDROBIOPTERIN-DEFICIENT, DUE TO GTP CYCLOHYDROLASE I DEFICIENCY; Hyperphenylalaninemia, BH4-Deficient, B; Hyperphenylalaninemia, tetrahydrobiopterin-deficient, due to GTP cyclohydrolase 1 deficiency
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

GTP-cyclohydrolase I deficiency, an autosomal recessive genetic disorder, is one of the causes of malignant hyperphenylalaninemia due to tetrahydrobiopterin deficiency. Not only does tetrahydrobiopterin deficiency cause hyperphenylalaninemia, it is also responsible for defective neurotransmission of monoamines because of malfunctioning tyrosine and tryptophan hydroxylases, both tetrahydrobiopterin-dependent hydroxylases. [from ORDO]

Available tests

13 tests are in the database for this condition.

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Clinical tests (13 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: DYT14, DYT5, DYT5a, GCH, GTP-CH-1, GTPCH1, HPABH4B, GCH1
    Summary: GTP cyclohydrolase 1

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 Phenylalanine, Phenylalanine hydroxylase deficiency (PAH), 2022
  • ACMG Algorithm, 2022
    American College of Medical Genetics and Genomics, Algorithm, PAH deficiency: Elevated Phenylalanine, 2022

Molecular resources

Consumer resources

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