Zdravniški Vestnik (Jun 2003)
GENETIC POLYMORPHISM OF CYTOCHROMES P450 2C9 AND 2C19 IN SLOVENIAN POPULATION
Abstract
Background. Cytochrome P450 2C9 (CYP2C9) and 2C19 (CYP2C19) participate in metabolism of many clinically important drugs. Genetic polymorphisms of the CYP2C9 and CYP2C19 genes are described which may affect drug treatment. The aim of this study was to determine the frequencies of polymorphic CYP2C9 and CYP2C19 alleles in Slovenian population in order to estimate the proportion of the population that might experience adverse drug reaction.Methods. The polymorphism of CYP2C9 and CYP2C19 was analysed by a genotyping technique, based on polymerase chain reaction (PCR) followed by restriction enzyme analysis. DNA samples from 129 unrelated healthy subjects were obtained from the Blood Transfusion Centre of Slovenia and University Children’s Hospital in Ljubljana.Results. In the analysed group of samples one-third of individuals carried at least one of the defective CYP2C9 alleles while among them 3.2% of individuals had both alleles affected. The frequencies of CYP2C9*2 and CYP2C9*3 were 0.122 and 0.063, respectively. Almost one-third of Slovenian individuals analysed carried at least one of the CYP2C19 polymorphic allele. The frequencies of CYP2C19*2 and CYP2C19*3 were 0.159 and 0.004, respectively.Conclusions. The results of our study indicate that approximately one-third of the patients from Slovenian population may require either adjustments of dose or increased monitoring when initiating treatment with CYP2C9 and CYP2C19 substrates having a narrow therapeutic index. High risk of adverse drug reaction may be expected in 1–3% of eventual patients.
