Genetic polymorphism of the drug-metabolizing enzyme Cytochrome P4502E1 (CYP2E1) in a healthy Saudi population

OBJECTIVES: Cytochrome P450 2E1 (CYP2E1) is one of the major enzymes involved in the metabolism and detoxification of various drugs and xenobiotics. Polymorphisms in the CYP2E1 gene exhibit high inter-individual variations associated with alterations in CYP2E1 gene expression and enzyme function. This study aimed to determine the genotype distributions and allele frequencies of CYP2E1*1B, *5B, and *6 polymorphisms among Saudis in western Saudi Arabia. METHODS: In total, 140 healthy Saudis attending King Abdulaziz University Hospital between February and April 2021 were included in the study. CYP2E1 gene polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism analysis. RESULTS: The genotype frequencies of CYP2E1*1B A2A2, A2A1, and A1A1 were 54.29%, 40%, and 8%, respectively. The frequencies of CYP2E1*5B c1c1 and c1c2 genotypes were approximately 99.93% and 0.07%, respectively. The frequencies of the CYP2E1*6 DD, DC, and CC genotypes were 91.43%, 7.85%, and 0.72%, respectively. The genotype distributions for these polymorphisms were consistent with the expected distribution based on Hardy-Weinberg equilibrium. The allele frequencies were 74.29% A2 and 25.71% A1 for CYP2E1*1B, 99.64% c1 and 0.36% c2 for CYP2E1*5B, and 95.36% D and 4.65% C for CYP2E1*6. CONCLUSION: The genotype distribution of CYP2E1*1B polymorphism was higher in the western Saudi population, whereas the CYP2E1*5B and *6 polymorphisms were lower than the global average. Knowledge of the prevalence of CYP2E1 polymorphisms among our population will provide a better understanding of whether individual patients might benefit from their medication or whether they might develop adverse effects.