Genetic Polymorphisms of CYP2C9: Comparison of Prevalence in the Lebanese Population with Other Populations

There is little knowledge about genotyping of cytochrome P450s in the Middle East, and there has not been any report on the genotype of CYP2C9 allelic variants in Lebanese population. The purpose of the study was to determine and compare the frequencies of the cytochrome P450 CYP2C9 variants in the Lebanese population with the frequencies in other ethnic populations. CYP2C9 genotypes were determined in a total of 146 samples of unrelated, healthy Lebanese individuals residing in different areas in Lebanon. Following DNA extraction from buccal cells and polymerase chain reaction, genotyping was performed by Pyrosequencing method. The frequencies of the CYP2C29*2, CYP2C9*3, and CYP2C9*4 alleles were 11.305%, 11.645%, and 1.025% respectively. This is the first report from Lebanon on CYP2C9 variants; it highlights a higher frequency of CYP2C9 extensive metabolizers compared to other populations including Caucasians. The results serve as a database on CYP 2C9 polymorphisms and baseline clinical data for dosing and avoiding adverse drug reactions of drugs metabolized by CYP2C9 in Lebanese patients.