This gene encodes a member of the aromatic amino acid hydroxylase family. The encoded protein catalyzes the first and rate limiting step in the biosynthesis of serotonin, an important hormone and neurotransmitter. Mutations in this gene have been associated with an elevated risk for a variety of diseases and disorders, including schizophrenia, somatic anxiety, anger-related traits, bipolar disorder, suicidal behavior, addictions, and others.[provided by RefSeq, Apr 2009],catalytic activity:L-tryptophan + tetrahydrobiopterin + O(2) = 5-hydroxy-L-tryptophan + 4a-hydroxytetrahydrobiopterin.,cofactor:Fe(2+) ion.,pathway:Aromatic compound metabolism, serotonin biosynthesis, serotonin from L-tryptophan: step 1/2.,similarity:Belongs to the biopterin-dependent aromatic amino acid hydroxylase family.,similarity:Contains 1 ACT domain.,subunit:Multimer of identical subunits.,tissue specificity:Isoform 2 seems to be less widely expressed than isoform 1.,
