Background: Cytochrome P450 2A6 enzyme (CYP2A6), an essential hepatic enzyme involved in the
metabolism of drugs, is responsible for a major metabolic pathway of nicotine. Variation in the activity of polymorphic
CYP2A6 alleles has been implicated in inter-individual differences in nicotine metabolism.
Aims: The objective of the current study was to assess the association between the smoking status and the cytochrome
P450 2A6 enzyme (CYP2A6) genotype in Jordanians.
Methods: In the current study, 218 (117 Male and 101 female) healthy unrelated Jordanian volunteers were recruited.
CYP2A6*1B, CYP2A6*4 and CYP2A6*9 were determined and correlated with subject smoking status.
Results: *1A/*1A was the most common genetic polymorphism in the overall study population, with no significant
frequency differences between smokers and non-smokers. When the population was divided according to gender,
only male smokers showed a significant correlation between genotype and smoking status. Considering the
CYP2A6*9 genotype, the results showed differences in distribution between smokers and non-smokers, but only
women showed a significant association between CYP2A6*9 allele genotype and smoking status.
Conclusion: The results of this study show that there is a significant association between CYP2A6*9 genotype and
smoking status. They also show that CYP2A6 genotype is significantly influenced by gender.