Pathway candidateNCBI-verifiedprotein-coding

TPH2

tryptophan hydroxylase 2

NCBI Gene: 121278 Ensembl GeneCards UniProt: Q8IWU9

Pathway candidate — not linked to PFS or PSSD by any record here

TPH2 is in the library because it belongs to the neurotransmission family. No study, report or commentary in the corpus names it, so a variant in TPH2 is not, by itself, evidence of anything related to post-drug syndromes.

Gene summary

A protein-coding gene on chromosome 12 (neurotransmission). Encodes a member of the pterin-dependent aromatic acid hydroxylase family. The protein catalyzes the first and rate limiting step in the biosynthesis of serotonin, an important hormone and neurotransmitter.

Source: NCBI Gene, accessed 2026-10-07.

Protein reference (UniProt)

Protein: Tryptophan 5-hydroxylase 2
Function: Neuron-specific enzyme that catalyzes the conversion of L-tryptophan into 5-hydroxy-L-tryptophan, the rate-limiting step in serotonin production, using Fe(2+) as cofactor and molecular oxygen and tetrahydrobiopterin (BH4) as cosubstrates. Plays a crucial role in regulating mood, anxiety and sleep (By similarity).
Pathway: Aromatic compound metabolism; serotonin biosynthesis; serotonin from L-tryptophan: step 1/2.
Tissue specificity: Brain specific.
Associated conditions: Major depressive disorder (MDD); Attention deficit-hyperactivity disorder 7 (ADHD7).

Source: UniProtKB/Swiss-Prot Q8IWU9, release 2026_03, licensed CC BY 4.0. This is the protein’s normal biology, not evidence about post-drug syndromes; associated conditions are inherited disorders of the gene, not PFS, PSSD or PRSD.

Why its pathway is in the library

Monoamine, GABA, glutamate, and cholinergic systems are the direct pharmacologic targets of SSRIs/SNRIs (PSSD) and the downstream effectors of neurosteroid signaling (PFS).

Written for the whole neurotransmission family, not for TPH2 specifically.

Mentioned in 0 corpus records

No corpus record names TPH2 directly yet. It is in the library because it sits in a pathway the corpus tracks (Neurotransmission).

Also in neurotransmission

All 54 genes

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Gene summary

Source: NCBI Gene, accessed 2026-10-07.

Protein reference (UniProt)

Protein: Tryptophan 5-hydroxylase 2
Function: Neuron-specific enzyme that catalyzes the conversion of L-tryptophan into 5-hydroxy-L-tryptophan, the rate-limiting step in serotonin production, using Fe(2+) as cofactor and molecular oxygen and tetrahydrobiopterin (BH4) as cosubstrates. Plays a crucial role in regulating mood, anxiety and sleep (By similarity).
Pathway: Aromatic compound metabolism; serotonin biosynthesis; serotonin from L-tryptophan: step 1/2.
Tissue specificity: Brain specific.
Associated conditions: Major depressive disorder (MDD); Attention deficit-hyperactivity disorder 7 (ADHD7).