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Primary topic: NOS3 nitric oxide gene

NOS3 Gene and Metabolism: What It Means for Your Body

NOS3 is relevant when circulation, endothelial function, and nitric-oxide-related performance response seem harder to optimize than expected.

What is the NOS3 gene?

NOS3 encodes endothelial nitric oxide synthase, which helps produce nitric oxide in blood vessels. This affects vascular tone, blood flow, and how well tissues receive oxygen and nutrients.

How NOS3 affects metabolism

If NOS3-related signaling is less efficient, vascular response and endothelial support may be less robust. That can matter for exercise tolerance, blood-pressure context, and recovery quality.

What happens when NOS3 is altered

Altered NOS3 function usually shifts physiological tendencies rather than creating a simple binary state. The value is in knowing whether vascular support deserves follow-up.

Curated SNP evidence for NOS3

These SNPs come from the approved study-level evidence model. Each claim is scored from curated study rows, then gated before it can influence pathway scoring.

Mitochondrial energy Nitric oxide / vascular tone Oxidative stress

Evidence-backed report connection

NOS3 currently has 2 curated SNPs, 6 claim-level scores, and 1 claims eligible for pathway scoring.

Open the sample report
rs1799983Glu298Asp3 claims · 9 study rows

enzyme activity · TT

NOS3 enzyme activity

Moderate

rs1799983 TT is associated with reduced NOS3 enzyme activity.

NOS3 rs1799983 is scored as a cautious tendency toward lower endothelial nitric oxide synthase activity for T-containing genotypes, strongest for TT.

Likely effectLower enzyme activity signal
Signal sizeSmall signal
Evidence supportModerate support
Report useIncluded in pathway scoring
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP identifies rs1799983 in NOS3 and annotates the common G and T alleles with the endothelial nitric oxide synthase Glu298Asp protein difference. This record scores the common G/T genotype set for a simplified NOS3 functional tendency.PubMed 17449720functional assay · directJoshi et al. studied human endothelial cells by NOS3 Glu298Asp genotype and found that Asp-variant genotypes had lower nitric oxide metabolite production before and after shear exposure, with altered NOS3 caveolar localization and impaired shear response. This supports a lower NOS3 activity tendency for T-containing genotypes.PubMed 37451608review · directA 2023 systematic review and meta-analysis notes that published studies have reported lower circulating nitric oxide with the NOS3 Glu298Asp polymorphism, while clinical association results vary by ancestry and endpoint. This supports keeping the effect as a cautious enzyme-activity tendency rather than a disease prediction.

enzyme activity · GT

NOS3 enzyme activity

Not used for pathway scoring

rs1799983 GT is associated with reduced NOS3 enzyme activity.

NOS3 rs1799983 is scored as a cautious tendency toward lower endothelial nitric oxide synthase activity for T-containing genotypes, strongest for TT.

Likely effectLower enzyme activity signal
Signal sizeSmall signal
Evidence supportModerate support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP identifies rs1799983 in NOS3 and annotates the common G and T alleles with the endothelial nitric oxide synthase Glu298Asp protein difference. This record scores the common G/T genotype set for a simplified NOS3 functional tendency.PubMed 17449720functional assay · directJoshi et al. studied human endothelial cells by NOS3 Glu298Asp genotype and found that Asp-variant genotypes had lower nitric oxide metabolite production before and after shear exposure, with altered NOS3 caveolar localization and impaired shear response. This supports a lower NOS3 activity tendency for T-containing genotypes.PubMed 37451608review · directA 2023 systematic review and meta-analysis notes that published studies have reported lower circulating nitric oxide with the NOS3 Glu298Asp polymorphism, while clinical association results vary by ancestry and endpoint. This supports keeping the effect as a cautious enzyme-activity tendency rather than a disease prediction.

enzyme activity · GG

NOS3 enzyme activity

Not used for pathway scoring

rs1799983 GG has no scored directional claim for NOS3 enzyme activity.

NOS3 rs1799983 is scored as a cautious tendency toward lower endothelial nitric oxide synthase activity for T-containing genotypes, strongest for TT.

Likely effectNo clear enzyme signal
Signal sizeMinimal signal
Evidence supportVery limited support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP identifies rs1799983 in NOS3 and annotates the common G and T alleles with the endothelial nitric oxide synthase Glu298Asp protein difference. This record scores the common G/T genotype set for a simplified NOS3 functional tendency.PubMed 17449720functional assay · directJoshi et al. studied human endothelial cells by NOS3 Glu298Asp genotype and found that Asp-variant genotypes had lower nitric oxide metabolite production before and after shear exposure, with altered NOS3 caveolar localization and impaired shear response. This supports a lower NOS3 activity tendency for T-containing genotypes.PubMed 37451608review · directA 2023 systematic review and meta-analysis notes that published studies have reported lower circulating nitric oxide with the NOS3 Glu298Asp polymorphism, while clinical association results vary by ancestry and endpoint. This supports keeping the effect as a cautious enzyme-activity tendency rather than a disease prediction.
rs2070744NOS3 promoter signal, NOS3 supporting signal3 claims · 9 study rows

expression · CC

NOS3 gene expression

Not used for pathway scoring

rs2070744 CC is associated with reduced NOS3 gene expression.

NOS3 rs2070744 is scored as a tendency toward lower NOS3 expression for C-containing genotypes, strongest for CC.

Likely effectLower gene expression signal
Signal sizeSmall signal
Evidence supportLimited support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP identifies rs2070744 in NOS3, with common C and T alleles and transcript annotations consistent with a noncoding promoter-region variant. This record scores a simplified expression tendency rather than a protein-coding enzyme change.PubMed 10359729functional assay · directNakayama et al. reported that the NOS3 T-786C promoter change significantly reduced NOS3 promoter activity in luciferase reporter assays. This supports a lower NOS3 expression tendency for C-containing genotypes, with stronger scoring for CC than CT.ClinVar recordclinical curation · directClinVar links rs2070744 to NOS3 and literature-only cardiovascular susceptibility submissions, but it does not provide expression assay evidence. It is retained as clinical context and not scored for the expression direction.

expression · CT

NOS3 gene expression

Not used for pathway scoring

rs2070744 CT is associated with reduced NOS3 gene expression.

NOS3 rs2070744 is scored as a tendency toward lower NOS3 expression for C-containing genotypes, strongest for CC.

Likely effectLower gene expression signal
Signal sizeSmall signal
Evidence supportLimited support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP identifies rs2070744 in NOS3, with common C and T alleles and transcript annotations consistent with a noncoding promoter-region variant. This record scores a simplified expression tendency rather than a protein-coding enzyme change.PubMed 10359729functional assay · directNakayama et al. reported that the NOS3 T-786C promoter change significantly reduced NOS3 promoter activity in luciferase reporter assays. This supports a lower NOS3 expression tendency for C-containing genotypes, with stronger scoring for CC than CT.ClinVar recordclinical curation · directClinVar links rs2070744 to NOS3 and literature-only cardiovascular susceptibility submissions, but it does not provide expression assay evidence. It is retained as clinical context and not scored for the expression direction.

expression · TT

NOS3 gene expression

Not used for pathway scoring

rs2070744 TT has no scored directional claim for NOS3 gene expression.

NOS3 rs2070744 is scored as a tendency toward lower NOS3 expression for C-containing genotypes, strongest for CC.

Likely effectNo clear expression signal
Signal sizeMinimal signal
Evidence supportVery limited support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP identifies rs2070744 in NOS3, with common C and T alleles and transcript annotations consistent with a noncoding promoter-region variant. This record scores a simplified expression tendency rather than a protein-coding enzyme change.PubMed 10359729functional assay · directNakayama et al. reported that the NOS3 T-786C promoter change significantly reduced NOS3 promoter activity in luciferase reporter assays. This supports a lower NOS3 expression tendency for C-containing genotypes, with stronger scoring for CC than CT.ClinVar recordclinical curation · directClinVar Variation ID 14016 links rs2070744 to NOS3 and includes literature-only cardiovascular susceptibility submissions. Because the clinical entries are not diagnostic assertions and the variant is noncoding, this file limits the interpretation to expression tendency.

Common symptoms people report

  • exercise response that feels weaker than expected
  • cold hands or peripheral circulation concerns
  • recovery that seems limited by flow or endurance tolerance
  • interest in nitric-oxide support without clear validation

Biomarkers to validate

Blood pressure trends

Important practical context for endothelial function.

Lipid and inflammatory markers

Helpful because vascular function rarely acts in isolation.

Exercise tolerance tracking

Useful when nitric-oxide questions are performance-related.

Where DNA analysis helps

DNA can flag nitric-oxide-related pathways that might deserve attention, especially when recovery or vascular response questions keep recurring.

Example Insight

Your endothelial-response pathway may have less reserve than expected under training or recovery demand.

Suggested validation: blood pressure and exercise-response tracking.

What to do next

  • Validate the broader cardiovascular context rather than focusing on one performance supplement theory.
  • Use blood-pressure and exercise-response tracking before assuming nitric oxide is the bottleneck.
  • Compare NOS3 with oxidative-stress and lipid pathways when vascular questions overlap.

Upload your DNA file and receive a structured metabolic pathway analysis with prioritized insights and suggested validation markers.

Get My DNA Report

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