{{Rsnum
|rsid=3783637
|Gene=GCH1
|Chromosome=14
|position=54881400
|Orientation=plus
|GMAF=0.1795
|Gene_s=GCH1
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|geno1=(C;C)
|geno2=(C;T)
|geno3=(T;T)
}}{{ population diversity
| geno1=(C;C)
| geno2=(C;T)
| geno3=(T;T)
| CEU | 81.4 | 16.8 | 1.8
| HCB | 29.9 | 53.3 | 16.8
| JPT | 56.6 | 35.4 | 8.0
| YRI | 80.3 | 19.0 | 0.7
| ASW | 70.2 | 26.3 | 3.5
| CHB | 29.9 | 53.3 | 16.8
| CHD | 27.5 | 50.5 | 22.0
| GIH | 49.5 | 43.6 | 6.9
| LWK | 76.4 | 21.8 | 1.8
| MEX | 67.2 | 32.8 | 0.0
| MKK | 81.4 | 17.9 | 0.6
| TSI | 80.4 | 18.6 | 1.0
| HapMapRevision=28
}}{{PMID Auto GWAS
|PMID=22446963
|Trait=None
|Title=Meta-analysis identifies nine new loci associated with rheumatoid arthritis in the Japanese population.
|RiskAllele=C
|Pval=0.000002
|OR=1.1000
|ORtxt=None
}}

{{PMID Auto
|PMID=17343757
|Title=Lack of influence of GTP cyclohydrolase gene (GCH1) variations on pain sensitivity in humans.
|OA=1
}}

{{PMID Auto GWAS
  |PMID=23251661
  |Trait=Obesity-related traits
  |Title=Novel genetic loci identified for the pathophysiology of childhood obesity in the Hispanic population.
  |RiskAllele=A
  |Pval=1E-6
  |OR=.03
  |ORtxt=[NR]  nmol/d increase
  |OA=1
}}

{{on chip | 23andMe v1}}
{{on chip | 23andMe v2}}
{{on chip | 23andMe v3}}
{{on chip | 23andMe v4}}
{{on chip | FTDNA2}}
{{on chip | HumanOmni1Quad}}
{{on chip | Illumina Human 1M}}