Genetic Polymorphism of Microsomal Epoxide Hydrolase Enzyme Gene in Preeclamptic Females

Introduction: Microsomal epoxide hydrolase enzyme is involved in xenobiotics detoxification. It catalyzes the phase I hydrolysis of epoxides and plays a role in the detoxification processes and in the metabolism of endogenous and exogenous compounds. Preeclampsia, which is one of the most serious complications of pregnancy, may be due to an imbalance between these compounds, such as lipid peroxides and oxygen-free radicals and detoxifying and scavenging substances. Two variants of human epoxide hydrolase enzyme with different enzyme activity have been described; exon 3 polymorphism is associated with lower enzyme activity whereas exon 4 polymorphism is associated with higher activity. The authors tried to investigate the association between these genetic polymorphisms and preeclampsia. Method: Thirty preeclamptic females together with 30 normal pregnant females as controls were included in the study. Genotyping for exons 3 and 4 of microsomal epoxide hydrolase enzyme was done by polymerase chain reaction-restriction fragment length polymorphism. Results: There was no statistical significant difference in the distribution of exon 3 genotype between cases and controls (P = 0.4); on the other hand, a highly statistical significant difference was found between cases and controls as regard exon 4 genotype (P = 0.002). Conclusion: There may be an association between epoxide hydrolase enzyme polymorphism and the risk of preeclampsia.