Caffeine metabolism (plasma 1,7-dimethylxanthine (paraxanthine) to 1,3,7-trimethylxanthine (caffeine) ratio)
CYP2A6 · rs66500423
0 4222217123121Reads by AI crawlersClaude2ChatGPT2Google · Gemini2Perplexity1Meta AI7Microsoft · Copilot1Amazon2Apple3China (ByteDance, Huawei, Baidu…)1ByteDance (Doubao)1Others21Total42Counted by the name each crawler declares; requests found to be impersonating one are left out. Google · Gemini includes Googlebot, the search crawler whose index Google also uses for its AI features. Other search engines and bots are under Others.
Who was studied 5,323 European ancestry individuals; replicated in 824 European ancestry individuals.
The effect
Each copy of the T allele shifted the measure 5.83 Z-score higher (95% confidence interval -); p = 6 × 10−9.
How common The T allele had a frequency of about 67% in the people studied.
Where it sits Chromosome 19, band 19q13.2 — in an intron of NUMBL.
What each result means
C/CNo copy of the version the research linked to Caffeine metabolism (plasma 1,7-dimethylxanthine (paraxanthine) to 1,3,7-trimethylxanthine (caffeine) ratio). This is the starting point the study compared everyone against.
C/TOne copy of the version the research linked to Caffeine metabolism (plasma 1,7-dimethylxanthine (paraxanthine) to 1,3,7-trimethylxanthine (caffeine) ratio). That is a smaller link than two copies.
T/TTwo copies of the version the research linked to Caffeine metabolism (plasma 1,7-dimethylxanthine (paraxanthine) to 1,3,7-trimethylxanthine (caffeine) ratio). That is the strongest link of the three results. A link in a study is not a diagnosis.
rs66500423 is a single position in the genome, in or near the CYP2A6 gene. Published research associates it with caffeine metabolism (plasma 1,7-dimethylxanthine (paraxanthine) to 1,3,7-trimethylxanthine (caffeine) ratio). A single variant does not decide an outcome — it shifts a probability, and for most common variants the shift is small.
Does rs66500423 affect how medicines work?
CYP2A6 carries pharmacogenomic findings for Smoking cessation medicines. That is educational information, not a prescription or a dosing guide. Any decision to start, stop or change a medicine belongs with the clinician or pharmacist managing your treatment.
Does having rs66500423 mean I will get this?
No. Common variants like this one move a probability slightly and, on their own, rarely decide anything about one person. Nothing on this page is a diagnosis, and health decisions should be made with a clinician who can see your whole picture.
Where does the information about rs66500423 come from?
GWAS Catalog, Hum Mol Genet 2016, PMID:27702941. Every variant on MyGeneLog comes from public primary sources and is published with its citation and the date it was checked.
0 4222217123121Reads by AI crawlersClaude2ChatGPT2Google · Gemini2Perplexity1Meta AI7Microsoft · Copilot1Amazon2Apple3China (ByteDance, Huawei, Baidu…)1ByteDance (Doubao)1Others21Total42Counted by the name each crawler declares; requests found to be impersonating one are left out. Google · Gemini includes Googlebot, the search crawler whose index Google also uses for its AI features. Other search engines and bots are under Others.
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