NCIt definition : Human GCH1 wild-type allele is located in the vicinity of 14q22.2 and is approximately
61 kb in length. This allele, which encodes GTP cyclohydrolase 1 protein, plays a
role in GTP metabolism and tetrahydrobiopterin biosynthesis. Mutation of the gene
is associated with autosomal dominant dopa-responsive dystonia and BH4-deficient hyperphenylalaninemia
B.;