• dehydratase
  • Other underlying causes of tetrahydrobiopterin deficiency are: 6-Pyruvoyl tetrahydropterin synthase (PTPS) deficiency Autosomal recessive guanosine triphosphate cyclohydrolase I (GTPCH) deficiency Pterin-4alpha-carbinolamine dehydratase (PCD) deficiency Treatment of THB deficiencies consists of THB supplementation (2-20 mg/kg per day) or diet to control blood phenylalanine concentration and replacement therapy with neurotransmitters precursors (L-DOPA and 5-HTP) and supplements of folinic acid in DHPR deficiency. (wikipedia.org)