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Primary topic: IRS1 insulin signaling gene

IRS1 Gene and Metabolism: What It Means for Your Body

IRS1 sits close to the center of insulin signaling, making it highly relevant when carb response and metabolic flexibility are in question.

What is the IRS1 gene?

IRS1 helps transmit the insulin signal inside cells. That means it affects how well tissues respond when insulin is trying to move glucose into use or storage.

How IRS1 affects metabolism

If IRS1-related signaling is weaker, glucose handling may require more effort. Over time this can show up as post-meal fatigue, appetite issues, or weight-related friction.

What happens when IRS1 is altered

Altered IRS1 function is not a diagnosis of insulin resistance, but it can make glucose-response follow-up much more worth doing than generic dieting advice alone.

Curated SNP evidence for IRS1

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.

Glucose

Evidence-backed report connection

IRS1 currently has 3 curated SNPs, 10 claim-level scores, and 2 claims eligible for pathway scoring.

Open the sample report
rs1801278IRS1 Gly972Arg1 claims · 2 study rows

biomarker tendency · A

insulin resistance biomarker tendency

Moderate

rs1801278 A / Arg972 carrier status is associated with higher insulin resistance biomarker tendency.

IRS1 rs1801278 A is staged as an insulin-resistance biomarker allele, not as a disease-risk-only claim.

Likely effectHigher biomarker tendency
Signal sizeSmall signal
Evidence supportStrong support
Report useIncluded in pathway scoring
Show study evidence
PMCID PMC6167972biomarker association · directThe checked IRS1 source identifies rs1801278 G>A / Gly972Arg and reports that GA+AA genotypes and the A allele were enriched in insulin-resistant versus insulin-sensitive T2DM participants with higher HOMA-IR context.PMCID PMC9408134biomarker association · directThe second checked source links IRS1 Gly972Arg / rs1801278 to obesity and insulin-resistance measures in PCOS; staged as supporting biomarker evidence only.
rs2943641IRS1 insulin-response signal6 claims · 18 study rows

expression · CC

IRS1 gene expression

Not used for pathway scoring

rs2943641 CC is associated with reduced IRS1 gene expression.

IRS1-near rs2943641 is scored as a lower IRS1 expression or signaling tendency for C-containing C/T genotypes, with the strongest score 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 data list rs2943641 with T, A, and C alleles. The main human metabolic studies cited here evaluate the common C/T contrast, so A-containing genotypes are kept neutral with low certainty.Evidence 2functional assay · loose proxyThe Nature Genetics study reported rs2943641 near IRS1 as associated with type 2 diabetes, insulin resistance, and hyperinsulinemia; it also reported that the C allele was associated with reduced basal IRS1 protein and reduced insulin-induced IRS1-associated phosphatidylinositol-3-OH kinase activity in human skeletal muscle biopsies.PubMed 21917432biomarker association · loose proxyThe follow-up study reported insulin and HOMA-IR associations by rs2943641 allele but did not measure IRS1 expression or protein abundance. It is retained as biomarker context and not scored for the expression claim.

expression · CT

IRS1 gene expression

Not used for pathway scoring

rs2943641 CT is associated with reduced IRS1 gene expression.

IRS1-near rs2943641 is scored as a lower IRS1 expression or signaling tendency for C-containing C/T genotypes, with the strongest score 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 data list rs2943641 with T, A, and C alleles. The main human metabolic studies cited here evaluate the common C/T contrast, so A-containing genotypes are kept neutral with low certainty.Evidence 2functional assay · loose proxyThe Nature Genetics study reported rs2943641 near IRS1 as associated with type 2 diabetes, insulin resistance, and hyperinsulinemia; it also reported that the C allele was associated with reduced basal IRS1 protein and reduced insulin-induced IRS1-associated phosphatidylinositol-3-OH kinase activity in human skeletal muscle biopsies.PubMed 21917432biomarker association · loose proxyThe follow-up study reported insulin and HOMA-IR associations by rs2943641 allele but did not measure IRS1 expression or protein abundance. It is retained as biomarker context and not scored for the expression claim.

expression · AA

IRS1 gene expression

Not used for pathway scoring

rs2943641 AA has no scored directional claim for IRS1 gene expression.

IRS1-near rs2943641 is scored as a lower IRS1 expression or signaling tendency for C-containing C/T genotypes, with the strongest score 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 data list rs2943641 with T, A, and C alleles. The main human metabolic studies cited here evaluate the common C/T contrast, so A-containing genotypes are kept neutral with low certainty.Evidence 2biomarker association · loose proxyThe Nature Genetics study reported rs2943641 near IRS1 as associated with type 2 diabetes, insulin resistance, and hyperinsulinemia; it also reported that the C allele was associated with reduced basal IRS1 protein and reduced insulin-induced IRS1-associated phosphatidylinositol-3-OH kinase activity in human skeletal muscle biopsies.PubMed 21917432biomarker association · loose proxyA follow-up study reported that the rs2943641 T allele was associated with lower fasting insulin, lower HOMA-IR, and lower post-load insulin in study cohorts, consistent with the C allele being the less favorable IRS1-linked signal for insulin-related biomarkers.

expression · AC

IRS1 gene expression

Not used for pathway scoring

rs2943641 AC has no scored directional claim for IRS1 gene expression.

IRS1-near rs2943641 is scored as a lower IRS1 expression or signaling tendency for C-containing C/T genotypes, with the strongest score 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 data list rs2943641 with T, A, and C alleles. The main human metabolic studies cited here evaluate the common C/T contrast, so A-containing genotypes are kept neutral with low certainty.Evidence 2biomarker association · loose proxyThe Nature Genetics study reported rs2943641 near IRS1 as associated with type 2 diabetes, insulin resistance, and hyperinsulinemia; it also reported that the C allele was associated with reduced basal IRS1 protein and reduced insulin-induced IRS1-associated phosphatidylinositol-3-OH kinase activity in human skeletal muscle biopsies.PubMed 21917432biomarker association · loose proxyA follow-up study reported that the rs2943641 T allele was associated with lower fasting insulin, lower HOMA-IR, and lower post-load insulin in study cohorts, consistent with the C allele being the less favorable IRS1-linked signal for insulin-related biomarkers.

expression · AT

IRS1 gene expression

Not used for pathway scoring

rs2943641 AT has no scored directional claim for IRS1 gene expression.

IRS1-near rs2943641 is scored as a lower IRS1 expression or signaling tendency for C-containing C/T genotypes, with the strongest score 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 data list rs2943641 with T, A, and C alleles. The main human metabolic studies cited here evaluate the common C/T contrast, so A-containing genotypes are kept neutral with low certainty.Evidence 2biomarker association · loose proxyThe Nature Genetics study reported rs2943641 near IRS1 as associated with type 2 diabetes, insulin resistance, and hyperinsulinemia; it also reported that the C allele was associated with reduced basal IRS1 protein and reduced insulin-induced IRS1-associated phosphatidylinositol-3-OH kinase activity in human skeletal muscle biopsies.PubMed 21917432biomarker association · loose proxyA follow-up study reported that the rs2943641 T allele was associated with lower fasting insulin, lower HOMA-IR, and lower post-load insulin in study cohorts, consistent with the C allele being the less favorable IRS1-linked signal for insulin-related biomarkers.

expression · TT

IRS1 gene expression

Not used for pathway scoring

rs2943641 TT has no scored directional claim for IRS1 gene expression.

IRS1-near rs2943641 is scored as a lower IRS1 expression or signaling tendency for C-containing C/T genotypes, with the strongest score 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 data list rs2943641 with T, A, and C alleles. The main human metabolic studies cited here evaluate the common C/T contrast, so A-containing genotypes are kept neutral with low certainty.Evidence 2biomarker association · loose proxyThe Nature Genetics study reported rs2943641 near IRS1 as associated with type 2 diabetes, insulin resistance, and hyperinsulinemia; it also reported that the C allele was associated with reduced basal IRS1 protein and reduced insulin-induced IRS1-associated phosphatidylinositol-3-OH kinase activity in human skeletal muscle biopsies.PubMed 21917432biomarker association · loose proxyA follow-up study reported that the rs2943641 T allele was associated with lower fasting insulin, lower HOMA-IR, and lower post-load insulin in study cohorts, consistent with the C allele being the less favorable IRS1-linked signal for insulin-related biomarkers.
rs7578326IRS1 supporting signal3 claims · 12 study rows

expression · AA

IRS1 gene expression

Moderate

rs7578326 AA is associated with reduced IRS1 gene expression.

IRS1-near rs7578326 is scored as a lower IRS1 expression tendency for A-containing genotypes, with a stronger score for AA than AG.

Likely effectLower gene expression signal
Signal sizeModerate signal
Evidence supportLimited support
Report useIncluded in pathway scoring
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP data list rs7578326 as an A/G variant, supporting use of AA, AG, and GG genotype letters in this file.Evidence 2gwas · loose proxyGWAS Catalog association data report rs7578326-A near IRS1 for type 2 diabetes. This supports metabolic relevance but does not directly support an IRS1 expression direction, so the row is neutral for the exact expression claim.PMC3080658expression eqtl · directThe large type 2 diabetes association study includes rs7578326 at the IRS1 locus and reports the A allele with lower IRS1 adipose expression in an expression analysis. This supports a cautious lower-expression direction for A-containing genotypes.PubMed 33505025expression eqtl · directA functional regulatory-variant study highlighted rs7578326 as a type 2 diabetes GWAS lead SNP predicted to target IRS1, with regulatory evidence in liver-derived cells and expression quantitative trait evidence in liver and adipose tissues. This supports the IRS1 expression target but not a standalone disease prediction.

expression · AG

IRS1 gene expression

Not used for pathway scoring

rs7578326 AG is associated with reduced IRS1 gene expression.

IRS1-near rs7578326 is scored as a lower IRS1 expression tendency for A-containing genotypes, with a stronger score for AA than AG.

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 data list rs7578326 as an A/G variant, supporting use of AA, AG, and GG genotype letters in this file.Evidence 2gwas · loose proxyGWAS Catalog association data report rs7578326-A near IRS1 for type 2 diabetes. This supports metabolic relevance but does not directly support an IRS1 expression direction, so the row is neutral for the exact expression claim.PMC3080658expression eqtl · directThe large type 2 diabetes association study includes rs7578326 at the IRS1 locus and reports the A allele with lower IRS1 adipose expression in an expression analysis. This supports a cautious lower-expression direction for A-containing genotypes.PubMed 33505025expression eqtl · directA functional regulatory-variant study highlighted rs7578326 as a type 2 diabetes GWAS lead SNP predicted to target IRS1, with regulatory evidence in liver-derived cells and expression quantitative trait evidence in liver and adipose tissues. This supports the IRS1 expression target but not a standalone disease prediction.

expression · GG

IRS1 gene expression

Not used for pathway scoring

rs7578326 GG has no scored directional claim for IRS1 gene expression.

IRS1-near rs7578326 is scored as a lower IRS1 expression tendency for A-containing genotypes, with a stronger score for AA than AG.

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 data list rs7578326 as an A/G variant, supporting use of AA, AG, and GG genotype letters in this file.Evidence 2gwas · loose proxyGWAS Catalog association data report rs7578326-A near IRS1 for type 2 diabetes. This supports metabolic relevance but does not directly support an IRS1 expression direction, so the row is neutral for the exact expression claim.PMC3080658expression eqtl · directThe large type 2 diabetes association study includes rs7578326 at the IRS1 locus and reports the A allele with lower IRS1 adipose expression in an expression analysis. This supports a cautious lower-expression direction for A-containing genotypes.PubMed 33505025expression eqtl · directA functional regulatory-variant study highlighted rs7578326 as a type 2 diabetes GWAS lead SNP predicted to target IRS1, with regulatory evidence in liver-derived cells and expression quantitative trait evidence in liver and adipose tissues. This supports the IRS1 expression target but not a standalone disease prediction.

Common symptoms people report

  • fatigue after carb-heavy meals
  • weight gain that clusters with carb cravings
  • slower response to glucose-focused nutrition changes
  • concern that insulin sensitivity may be slipping

Biomarkers to validate

Fasting insulin

Best first-pass marker for checking whether insulin pressure is relevant.

HbA1c

Adds broader glucose context over time.

Post-meal glucose tracking

Helpful when meal response is more revealing than fasting values.

Where DNA analysis helps

DNA helps prioritize insulin signaling as a real follow-up target instead of treating all carb-related symptoms as vague metabolism complaints.

Example Insight

Your insulin-signaling pathway may be contributing more to carb-response friction than standard advice assumes.

Suggested validation: fasting insulin and post-meal glucose tracking.

What to do next

  • Validate fasting insulin before assuming the pathway is only theoretical.
  • Compare IRS1 with TCF7L2, FTO, and ADIPOQ when glucose and weight questions overlap.
  • Use meal-response data, not just fasting data, when symptoms are post-meal.

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

Get My DNA Report

Related pages

TCF7L2

TCF7L2 diabetes gene

ADIPOQ

ADIPOQ metabolism gene

Triglycerides

triglycerides and metabolic health

ApoB

ApoB and lipid risk

Glucose regulation pathway

glucose regulation pathway

Lipid transport pathway

lipid transport pathway

Genetic test for weight loss Europe

genetic test for weight loss Europe

Related symptom angle

Fatigue after eating carbs

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