rs3783641
A SNP in the GCH1 gene on chromosome 14. Its most notable genotype is T;T: common/normal
- Gene
- GCH1
- Location
- Chr 1454,893,421 (GRCh38)
- Highest magnitude
- 0.0Typical
- Tested on
- 23andMe, AncestryDNA
- Minor allele frequency
- 23%
Genotypes
As shown in 23andMe and AncestryDNA files.
On SNPedia: (T;T). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.
Frequency
Share of each genotype in 4 HapMap populations.
- AverageT;T 55%
- European ancestry (Utah)T;T 57%
- Han Chinese (Beijing)T;T 69%
- Japanese (Tokyo)T;T 66%
- Yoruba (Nigeria)T;T 29%
Related
Other GCH1 SNPs
- rs886039379-;ATDystonia, dopa-responsiveVery important
- rs41298442C;CDystonia (dopa-responsive) from homozygous GCH1 mutationVery important
- rs104894433A;Gdystonia due on GCH1 loss-of-function mutationVery important
- rs104894436A;CGCH1-deficient dopa-responsive dystonia (likely)Very important
- rs104894437A;Tdystonia due on GCH1 loss-of-function mutationVery important
- rs104894438C;Tdystonia due on GCH1 loss-of-function mutationVery important
- rs104894439C;Gdystonia due on GCH1 loss-of-function mutationVery important
- rs104894440G;Tdystonia due on GCH1 loss-of-function mutationVery important
Genosets
- Gs224Two copies of GCH1 variant associated with lower levels of tetrahydrobiopterinImportant
- Gs223One copy of GCH1 variant associated with lower levels of tetrahydrobiopterinWorth knowing
Genosets combine several genotypes. Twofold checks them in your report.
Notes
From SNPedia
Notes
GTP cyclohydrolase and tetrahydrobiopterin regulate pain sensitivity and persistence. A allele associated with higher tolerance to pain. Polymorphisms in the GTP cyclohydrolase gene (GCH1) are associated with ratings of capsaicin pain. A allele associated with higher tolerance to pain. Do genetic predictors of pain sensitivity associate with persistent widespread pain? A allele associated with higher pain tolerance. GCH1 haplotype determines vascular and plasma biopterin availability in coronary artery disease effects on vascular superoxide production and endothelial function. Part of a haplotype, rs10483639(C)-rs3783641(A)-rs8007267(T), associated with lower levels of tetrahydrobiopterin.
Source and license
Adapted from rs3783641 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.
SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.