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Published on: March 28, 2017
CYP2A6 genotypes and coumarin-oxidation phenotypes in a Thai population and their relationship to tobacco smoking
Wiratchanee Mahavorasirikul1, Wichittra Tassaneeyakul, Soisagwan Satarug
1Faculty of Allied Health Sciences, Thammasat University, Pathumtanee, Thailand.
Objective:
To investigate the association between polymorphisms in the human CYP2A6 gene, CYP2A6 enzyme activity and the influence of cigarette smoking in a Thai population.
Methods:
Coumarin (5 mg capsule) was administered to 194 healthy Thai subjects. Genetic variation of the CYP2A6 gene was identified using PCR methods. The excreted dose of 7-hydroxycoumarin (as a percentage of the urine concentration) 2 h after administration was calculated as an index of coumarin metabolism.
Results:
The frequencies of CYP2A6 alleles *1A, *1B, *4C, *7, *8, *9 and *10 were 34.0, 35.3, 9.3, 6.4, 0.5, 12.1 and 2.4%, respectively. Of the 194 subjects tested, the number (percentages) of Thai participants classified as ultra-rapid, extensive, intermediate and poor metabolizers were 8 (4.1%), 159 (82.0%) 22 (11.3%) and five (2.6%), respectively.
Conclusion:
A relationship between the interindividual differences in coumarin metabolism and genetic polymorphisms of the CYP2A6 gene was observed.
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