TPH1 Gene

What is the TPH1 gene?

TPH1 encodes tryptophan hydroxylase 1, a protein involved in peripheral serotonin biosynthesis. It belongs to the Neurotransmitter category and is part of the Histamine & MCAS biological cluster. TPH1 encodes tryptophan hydroxylase 1, the rate-limiting enzyme in serotonin synthesis in enterochromaffin cells of the gut.

Biological role and pathway

TPH1 is involved in the peripheral serotonin biosynthesis pathway, which plays a central role in regulating physiological processes relevant to immune defence, cellular energy, and systemic homeostasis. Genes within the Histamine & MCAS cluster work together to maintain balanced function across interconnected biological systems.

Variants in genes within this pathway may influence an individual's predisposition to altered function in these systems — particularly under conditions of physiological stress such as viral infection or prolonged illness.

Known genetic variants

The following variants (SNPs) in the TPH1 gene have been studied in relation to neurotransmitter and chronic illness. Each variant represents a single nucleotide position where individuals may carry different alleles.

• rs1800532— TPH1 variant
• rs4537731— TPH1 variant

Conditions studied in relation to TPH1

Research into TPH1 variants has explored associations with the following conditions. These are areas of scientific investigation and do not imply that TPH1 causes or treats any condition.

Genetic insights from DNA data

Consumer DNA files from 23andMe, AncestryDNA, and MyHeritage contain raw SNP data. When you upload your file to ChronicDNA, the analysis engine checks your genotype against a curated panel of 80+ genes selected for their relevance to Long COVID, ME/CFS, and connected biological pathways - some of which may include TPH1 and related genes in the histamine & mcas pathway.

The report is educational - it explains which variants you carry, what the research says about them, and how they fit into the biological pathways most relevant to chronic illness. Results are presented in plain English with appropriate scientific context, no medical jargon, no scare tactics. All results should be discussed with a qualified healthcare provider.

Related genes in the Histamine & MCAS pathway

TPH1 does not act in isolation. The following genes are functionally related and may be analysed together for a more complete picture of your genetic predispositions.

Frequently asked questions