Objective CYP2J2 is the major enzyme responsible for the formation of epoxyeicosatrienoic acids (EETs) in the heart, the EETs are potent endogenous vasodilators and inhibitors of vascular inflammation. The CYP2J2 G-50T polymorphism has been shown to be associated with increased risk of coronary artery disease (CAD) via lower plasma concentrations of EETs, while there are currently some population-based studies which found controversial results. The aim of the study was to assess associations between the G-50T polymorphism of CYP2J2 and CAD via a case-control study in the Han population of China.

Methods There were 249 CAD patients and 243 age-matched control subjects genotyped for the CYP2J2 G-50T polymorphism. The data were assessed for three separate groups: the total subjects, men and women.

Results In total, the distribution of the dominant model of G-50T promoter (G/G versus GT+TT) was significantly lower in CAD patients than control subjects (p=0.048), and simultaneously the T allele was significantly lower in CAD patients than control subjects (p=0.037). However, logistic regression analysis failed to show that the GT+TT genotype was a protective factor for CAD (OR 0.477, 95% CI 0.175 to 1.299; p=0.148). We investigated the synergistic effect between G/T+T/T genotype and no smoking or no DM, finally results showed G/T+T/T genotype and no smoking had a tendency to be a synergistic effect (G/T+T/T genotype+no smoking OR=0.296 vs G/T+T/T genotype+smoking OR=0.730), while lacked sufficient statistical power (p=0.127, p=0.663, respectively).

Conclusions In presence of other risk factors, the CYP2J2 G-50T failed to show a significant association with coronary artery disease in Han population of China. However, since our result is close to the border of significance, further research based on the larger, prospective researches are necessary.