Evidence map›Paper›PMID 12534642›Full record

ArticleBritish journal of clinical pharmacology2003

Polymorphisms in the cytochrome P450 CYP1A2 gene (CYP1A2) in colorectal cancer patients and controls: allele frequencies, linkage disequilibrium and influence on caffeine metabolism.

Christoph Sachse, Upinder Bhambra, Gillian Smith, Tracy J Lightfoot, Jennifer H Barrett, Jenna Scollay, R Colin Garner, Alan R Boobis, C Roland Wolf, Nigel J Gooderham and 1 more

Open access · bronzeAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in British journal of clinical pharmacology, 2003. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 60 papers, 7 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
60citing papers in PubMed, 7 pooled it
14.4field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

60 citing papers in PubMed, 7 syntheses or guidelines pooled it, 172 citations in OpenAlex.

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  5. The effect of CYP1A1 and CYP1A2 polymorphisms on gastric cancer risk among different ethnicities: a systematic review and meta-analysis.Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine · 2014
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  8. CYP1A2, GSTM1, and GSTT1 polymorphisms and diet effects on CYP1A2 activity in a crossover feeding trial.Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology · 2009
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors at 5 institutions in 2 countries.

Christoph SachseBiomedical Research Centre, Ninewells Hospital & Medical School, Dundee, UK.
Upinder Bhambra
Gillian Smith
Tracy J Lightfoot
Jennifer H Barrett
Jenna Scollay
R Colin Garner
Alan R Boobis
C Roland Wolf
Nigel J Gooderham
Colorectal Cancer Study Group
Imperial College London · GBNinewells Hospital · GBSt James's University Hospital · GBUniversity of York · GBAustrian Breast & Colorectal Cancer Study Group · AT

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

aimsSeveral single nucleotide polymorphisms (SNPs) of the cytochrome P450 enzyme 1A2 gene (CYP1A2) have been reported. Here, frequencies, linkage disequilibrium and phenotypic consequences of six SNPs are described.

methodsFrom genomic DNA, 114 British Caucasians (49 colorectal cancer cases and 65 controls) were genotyped for the CYP1A2 polymorphisms -3858G-->A (allele CYP1A2*1C), -2464T-->delT (CYP1A2*1D), -740T-->G (CYP1A2*1E and *1G), -164A-->C (CYP1A2*1F), 63C-->G (CYP1A2*2), and 1545T-->C (alleles CYP1A2*1B, *1G, *1H and *3), using polymerase chain reaction-restriction fragment length polymorphism assays. All patients and controls were phenotyped for CYP1A2 by h.p.l.c. analysis of urinary caffeine metabolites.

resultsIn 114 samples, the most frequent CYP1A2 SNPs were 1545T-->C (38.2% of tested chromosomes), -164A-->C (CYP1A2*1F, 33.3%) and -2464T-->delT (CYP1A2*1D, 4.82%). The SNPs were in linkage disequilibrium: the most frequent constellations were found to be -3858G/-2464T/-740T/-164A/63C/1545T (61.8%), -3858G/-2464T/-740T/-164C/63C/1545C (33.3%), and -3858G/-2464delT/-740T/-164A/63C/1545C (3.51%), with no significant frequency differences between cases and controls. In the phenotype analysis, lower caffeine metabolic ratios were detected in cases than in controls. This was significant in smokers (n = 14, P = 0.020), and in a subgroup of 15 matched case-control pairs (P = 0.007), but it was not significant in nonsmokers (n = 100, P = 0.39). There was no detectable association between CYP1A2 genotype and caffeine phenotype.

conclusions(i) CYP1A2 polymorphisms are in linkage disequilibrium. Therefore, only -164A-->C (CYP1A2*1F) and -2464T-->delT (CYP1A2*1D) need to be analysed in the routine assessment of CYP1A2 genotype; (ii) in vivo CYP1A2 activity is lower in colorectal cancer patients than in controls, and (iii) CYP1A2 genotype had no effect on phenotype (based on the caffeine metabolite ratio). However, this remains to be confirmed in a larger study.

Indexed as

AgedAged, 80 and overCaffeineColorectal NeoplasmsCytochrome P-450 CYP1A2Gene FrequencyHumansLinkage DisequilibriumMiddle AgedPhenotypePolymerase Chain ReactionPolymorphism, GeneticCaffeineCytochrome P-450 CYP1A2

Identifiers

PMID12534642
PMCPMC1884179
OpenAlexW1560943036

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.