HPABH4B
Chr 14ARGTP cyclohydrolase 1
Also known as: DYT14, DYT5, DYT5a, GCH, GTP-CH-1, GTPCH1, HPABH4B
This gene encodes GTP cyclohydrolase I, the first and rate-limiting enzyme in tetrahydrobiopterin (BH4) biosynthesis, which catalyzes the conversion of GTP into 7,8-dihydroneopterin triphosphate. BH4 serves as an essential cofactor for aromatic amino acid hydroxylases and nitric oxide synthases. Mutations cause BH4-deficient hyperphenylalaninemia, which can present as malignant hyperphenylalaninemia or dopa-responsive dystonia, and follows autosomal recessive inheritance.
Primary Disease Associations & Inheritance
Some data sources returned errors (2)
ensembl: Error: Ensembl fetch failed: 400 for https://rest.ensembl.org/lookup/symbol/homo_sapiens/HPABH4B?content-type=application/json&expand=1
gnomad: Error: Gene not found
Population Genetics & Constraint
Constraint data not available from gnomAD.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
HPABH4B · protein map & ClinVar variants
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External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
No active trials found for this gene.
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External Resources
Links to major genomics databases and tools