title: Autosomal dominant GTP cyclohydrolase I (AD GCH 1) deficiency (Segawa disease, dystonia 5; DYT 5).
abstract: Autosomal dominant GTP cyclohydrolase I (AD GCH 1) deficiency (Segawa disease) is an autosomal dominant dopa responsive dystonia caused by heterozygous mutation of the GCH 1 gene located on 14q22.1-q22.2. Although a number of mutations have been reported, the change remains highly stable within families, and causes a decrease in the tyrosine hydroxylase protein at the nigrostriatal (NS)-dopamine (DA) neuron terminal. In addition, decreased tetrahydrobiopterin levels early in the development affect DA receptors age-dependently, and produce a spectrum of specific symptoms attributed to neuronal changes traced to processes in the development of the NS-DA neuron, related striatal projection neurons, and the output projection of the basal ganglia.
authors.affiliation: Segawa Neurological Clinic for Children, Tokyo, Japan. segawa@segawa-clinic.jp
authors.forename: Masaya
authors.initials: M
authors.lastname: Segawa
mesh_terms: D004421:Dystonia / Q000235:genetics*; D005260:Female; D006136:GTP Cyclohydrolase / Q000172:deficiency*; D006801:Humans; D008297:Male
chemical_list: D006136:GTP Cyclohydrolase