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Primary topic: CYP1A1 gene DNA analysis

CYP1A1 Gene and Metabolism: What It Can Mean in a Pathway Report

CYP1A1 becomes more useful when estrogen metabolism looks like a meaningful follow-up area instead of just background context.

What is the CYP1A1 gene?

CYP1A1 contributes to estrogen oxidation and broader xenobiotic overlap. That makes it more useful as part of a pathway view than as an isolated SNP call.

How CYP1A1 affects metabolism

If CYP1A1-related support is less favorable, the pathway can look more pressured under load and the linked biomarkers become more useful to validate directly.

What happens when CYP1A1 is altered

An altered CYP1A1 pattern does not diagnose anything on its own, but it does change which follow-up markers deserve attention first.

Curated SNP evidence for CYP1A1

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.

Estrogen metabolism

Evidence-backed report connection

CYP1A1 currently has 2 curated SNPs, 6 claim-level scores, and 0 claims eligible for pathway scoring.

Open the sample report
rs1048943I462V3 claims · 9 study rows

enzyme activity · CC

CYP1A1 enzyme activity

Not used for pathway scoring

rs1048943 CC is associated with increased CYP1A1 enzyme activity.

CYP1A1 rs1048943 is scored as a modest higher CYP1A1 enzyme-activity tendency for C-containing genotypes, strongest for CC.

Likely effectHigher enzyme activity signal
Signal sizeSmall signal
Evidence supportModerate support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP maps rs1048943 to CYP1A1 and shows that the C allele corresponds to the protein change p.Ile462Val in the current CYP1A1 transcript, while T is the Ile462 coding allele. This supports a CYP1A1 enzyme-activity record rather than an expression or biomarker record.PMC4601872other · close proxyA clinical genetics paper describes CYP1A1 rs1048943 as the A4889G CYP1A1*2C Ile462Val variant and states that the Val substitution has been associated with higher catalytic activity and mutagenicity. This supports increased activity scoring for Val-linked C-containing genotypes.PMC3429471review · close proxyA lung-cancer meta-analysis identifies rs1048943 as the CYP1A1 Ile462Val nonsynonymous variant involved in metabolism of polycyclic aromatic hydrocarbons and reports genotype associations that vary by ancestry, histology, and smoking status. This supports conservative certainty and avoids treating the genotype as a diagnosis.

enzyme activity · CT

CYP1A1 enzyme activity

Not used for pathway scoring

rs1048943 CT is associated with increased CYP1A1 enzyme activity.

CYP1A1 rs1048943 is scored as a modest higher CYP1A1 enzyme-activity tendency for C-containing genotypes, strongest for CC.

Likely effectHigher enzyme activity signal
Signal sizeSmall signal
Evidence supportModerate support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP maps rs1048943 to CYP1A1 and shows that the C allele corresponds to the protein change p.Ile462Val in the current CYP1A1 transcript, while T is the Ile462 coding allele. This supports a CYP1A1 enzyme-activity record rather than an expression or biomarker record.PMC4601872other · close proxyA clinical genetics paper describes CYP1A1 rs1048943 as the A4889G CYP1A1*2C Ile462Val variant and states that the Val substitution has been associated with higher catalytic activity and mutagenicity. This supports increased activity scoring for Val-linked C-containing genotypes.PMC3429471review · close proxyA lung-cancer meta-analysis identifies rs1048943 as the CYP1A1 Ile462Val nonsynonymous variant involved in metabolism of polycyclic aromatic hydrocarbons and reports genotype associations that vary by ancestry, histology, and smoking status. This supports conservative certainty and avoids treating the genotype as a diagnosis.

enzyme activity · TT

CYP1A1 enzyme activity

Not used for pathway scoring

rs1048943 TT has no scored directional claim for CYP1A1 enzyme activity.

CYP1A1 rs1048943 is scored as a modest higher CYP1A1 enzyme-activity tendency for C-containing genotypes, strongest for CC.

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 maps rs1048943 to CYP1A1 and shows that the C allele corresponds to the protein change p.Ile462Val in the current CYP1A1 transcript, while T is the Ile462 coding allele. This supports a CYP1A1 enzyme-activity record rather than an expression or biomarker record.PMC4601872other · close proxyA clinical genetics paper describes CYP1A1 rs1048943 as the A4889G CYP1A1*2C Ile462Val variant and states that the Val substitution has been associated with higher catalytic activity and mutagenicity. This supports increased activity scoring for Val-linked C-containing genotypes.PMC3429471review · close proxyA lung-cancer meta-analysis identifies rs1048943 as the CYP1A1 Ile462Val nonsynonymous variant involved in metabolism of polycyclic aromatic hydrocarbons and reports genotype associations that vary by ancestry, histology, and smoking status. This supports conservative certainty and avoids treating the genotype as a diagnosis.
rs4646903CYP1A1 supporting signal3 claims · 6 study rows

expression · GG

CYP1A1 gene expression

Not used for pathway scoring

rs4646903 GG is associated with increased CYP1A1 gene expression.

CYP1A1 rs4646903 is scored as a possible higher CYP1A1 expression tendency when the G allele is present, with a stronger score for GG than AG.

Likely effectHigher gene expression signal
Signal sizeModerate signal
Evidence supportLimited support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP places rs4646903 near CYP1A1 and shows A and G as the common observed allele labels in large population datasets. This supports limiting the record to CYP1A1 and the A/G genotype labels used here.PMC8310655other · loose proxyAn open full-text study of CYP1A1 rs4646903 describes this variant as a downstream 3-prime non-coding change and states that the variant form has been reported to increase CYP1A1 mRNA half-life, concentration, and enzymatic activity. The same paper also notes that its own cohort did not directly measure CYP1A1 mRNA or enzyme activity, so the functional interpretation remains conservative.

expression · AG

CYP1A1 gene expression

Not used for pathway scoring

rs4646903 AG is associated with increased CYP1A1 gene expression.

CYP1A1 rs4646903 is scored as a possible higher CYP1A1 expression tendency when the G allele is present, with a stronger score for GG than AG.

Likely effectHigher gene expression signal
Signal sizeSmall signal
Evidence supportLimited support
Report useEvidence only, not scored
Show study evidence
NCBI RefSNP recordidentity only · unknownNCBI RefSNP places rs4646903 near CYP1A1 and shows A and G as the common observed allele labels in large population datasets. This supports limiting the record to CYP1A1 and the A/G genotype labels used here.PMC8310655other · loose proxyAn open full-text study of CYP1A1 rs4646903 describes this variant as a downstream 3-prime non-coding change and states that the variant form has been reported to increase CYP1A1 mRNA half-life, concentration, and enzymatic activity. The same paper also notes that its own cohort did not directly measure CYP1A1 mRNA or enzyme activity, so the functional interpretation remains conservative.

expression · AA

CYP1A1 gene expression

Not used for pathway scoring

rs4646903 AA has no scored directional claim for CYP1A1 gene expression.

CYP1A1 rs4646903 is scored as a possible higher CYP1A1 expression tendency when the G allele is present, with a stronger score for GG 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 places rs4646903 near CYP1A1 and shows A and G as the common observed allele labels in large population datasets. This supports limiting the record to CYP1A1 and the A/G genotype labels used here.PMC8310655other · loose proxyAn open full-text study of CYP1A1 rs4646903 describes this variant as a downstream 3-prime non-coding change and states that the variant form has been reported to increase CYP1A1 mRNA half-life, concentration, and enzymatic activity. The same paper also notes that its own cohort did not directly measure CYP1A1 mRNA or enzyme activity, so the functional interpretation remains conservative.

Common symptoms people report

  • estrogen metabolism can overlap with more persistent symptom patterns
  • marker-driven follow-up may matter more than generic advice
  • mixed responses can make the pathway easier to miss without structured review

Biomarkers to validate

Estrogen metabolites

Primary follow-up marker for CYP1A1 inside estrogen metabolism.

Related pathway markers

Useful when the pathway needs to be validated as a system rather than as one variant.

Where DNA analysis helps

DNA helps decide whether CYP1A1 should move estrogen metabolism higher on the follow-up list before broad interventions are assumed.

Example interpretation

CYP1A1 can strengthen the case for estrogen metabolism follow-up when the rest of the pathway points in a similar direction.

Suggested validation: Estrogen metabolites.

What to do next

  • Use Estrogen metabolites and pathway context before assuming the gene matters in practice.
  • Read CYP1A1 alongside the related genes in the same pathway instead of as a standalone result.

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

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