Gene:
GTP cyclohydrolase 1 (dopa-responsive dystonia)
Gene ID:
208636
Symbol:
GCH1
Species:
1000
Description:
This gene encodes a member of the GTP cyclohydrolase I family. The encoded protein is the first and rate-limiting enzyme in tetrahydrobiopterin (BH4) biosynthesis, catalyzing the conversion of GTP into 7,8-dihydroneopterin triphosphate. BH4 is an essential cofactor required by aromatic amino acid hydroxylases as well as nitric oxide synthases. Mutations in this gene are associated with malignant hyperphenylalaninemia and dopa-responsive dystonia. Several alternatively spliced transcript variants encoding different isoforms have been described, however, only one gives rise to the functional enzyme.