Allele Frequency Distributions of the Drug Metabolizer Genes CYP2C9*2, CYP2C9*3, and CYP2C19*17 in the Buginese Population of Indonesia

The present study is part of the genetic mapping of Indonesia focusing on drug metabolizing enzymes, which started with the Buginese population of Makassar, South Sulawesi. The two CYP450 gene subfamilies, i.e. CYP2C9 and CYP2C19 are of interest as they exhibit wide inter-individual variation in expression, which influence the drug metabolism capacity. The CYP2C9 alleles of interest in this study were CYP2C9*2 and *3, and of CYP2C19 was CYP2C19. The study aimed to determine the frequencies of the CYP2C9 genotype, which contains *1, *2 and *3 alleles, and the CYP2C19 genotype, which comprises the *1 and *17 alleles in the Buginese. Ninety six Buginese subjects, comprising 48 males and 48 females were studied. CYP2C9 and CYP2C19 alleles were detected by a PCR-RFLP assay method. Results showed that there was no CYP2C9*2 allele present, while the frequencies of CYP2C9*3 and CYP2C19 overall were 1.56 % and 4.68 %, respectively. The frequency of the CYP2C9*3 allele in females was 2.08%, and not statistically different from that in males (1.05%). The frequency of the CYP2C19 allele in females (8.33%), was significantly different (P<0.05) from that in males (1.05%). No subject carried the CYP2C9*2/*2, CYP2C9*3/*3, CYP2C19*17/*17, or CYP2C9*3/CYP2C19 genotype. The study is the first to describe the drug metabolizing enzyme polymorphisms, CYP2C9 and CYP2C19, in the Indonesian Buginese population.