CYP1A2 inducibility
AA is commonly called a fast profile, CC a slow profile, and AC intermediate. The distinction is strongest under enzyme-inducing exposures.
Free calculator · CYP1A2
Caffeine metabolism calculator from raw DNA.
Interpret CYP1A2 rs762551 enzyme inducibility and, when available, keep the separate ADORA2A caffeine-response marker in context.
Is there a single ‘fast caffeine gene’?
Not exactly. CYP1A2 rs762551 is the best-studied common marker for enzyme inducibility, but smoking, medicines, hormones, pregnancy, liver health, and habitual caffeine use all matter. ADORA2A rs5751876 concerns sensitivity and anxiety response—not metabolism—and is reported separately.
Run the caffeine metabolism check
Choose the unmodified raw export from your provider. Only the listed marker calls are interpreted.
Supports 23andMe, AncestryDNA, FTDNA, MyHeritage, and Living DNA autosomal exports.
Drop your raw DNA file here
or.txt, .csv, .tsv, .zip, .gz · 30 MB max
What this calculator does—and does not do.
CYP1A2 carries out most caffeine metabolism. rs762551 changes how inducible the enzyme tends to be, but measured clearance remains an environment-sensitive phenotype.
ADORA2A response
The optional rs5751876 row describes a reported caffeine-anxiety association. It never changes the metabolism label.
No dosage advice
A genotype result cannot account for medication interactions, pregnancy, cardiovascular conditions, sleep, or an individual’s measured response.
Limitations
Where the model stops.
- The calculator estimates a tendency in enzyme inducibility, not caffeine half-life in hours.
- Smoking and several medicines can materially change CYP1A2 activity.
- There is no clinical dosing guideline that turns these two SNPs into a personalised safe caffeine limit.
Primary evidence
Research behind the panel.
- CYP1A2 systematic review and meta-analysisDenden et al., The Pharmacogenomics Journal (2017)
- ADORA2A controlled studyRogers et al., Neuropsychopharmacology (2010)
- Caffeine pathway reviewThorn et al., Pharmacogenetics and Genomics (2012)
Frequently asked.
Does AA always mean fast caffeine clearance?
No. AA is associated with higher inducibility on average, but current exposures and physiology can alter actual CYP1A2 activity.
Why show ADORA2A?
Caffeine can feel different even when metabolism is similar. ADORA2A is displayed as lower-confidence response context and never folded into CYP1A2 metabolism.
Can this tell me how much coffee is safe?
No. It is educational genetic context, not a dose recommendation or a substitute for medical advice.
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