Prevalence of CYP2C19 Polymorphisms in Clopidogrel Treated Turkish Patients: Preliminary Results, 2017

Background: Clopidogrel is one of the most frequently prescribed antiplatelet agents to reduce the risk of atherosclerotic symptoms. CYP2C19 enzyme is involved in clopidogrel metabolism, and several genetic variations of CYP2C19gene are able to affect the clinical response of clopidogrel. Despite the lack of a fully accepted guideline for CYP2C19 pharmacogenetic testing before clopidogrel treatment by relevant communities, we believe that determination of the variant frequencies is important to predict the efficiency and possible clopidogrel related risks before the initiation of treatment on the basis of populations. Our aim was to determine the distribution of gene polymorphisms affecting the enzyme activity in Turkish cardiac patients prescribed clopidogrel. Methods: 54 clopidogrel prescribed patients were included in the study. The presence of CYP2C19*2, *3, *4, *5, *6, *7, *8, *9, *10 and *17 polymorphisms were investigated using a microarray platform. Results : No variant allele was detected for *4, *5, *6, *7, *8, *9 and *10 polymorphisms. The genotype frequencies were detected as 38.89% for *1/*1, 16.67% for *1/*2, 11.11% for *2/*17, 1.85% for *1/*3, 1.85% for *2/*3, 27.78% for *1/*17 and 1.85% for *17/*17. According to genotype analysis, 1.85% of the patients were recorded as poor and 29.63% intermediate; whereas 27.78% as rapid and 1.85% ultra-rapid metabolizers. Conclusion: Although our study population does not consist of a high number of patients, since the high frequency of intermediate, rapid and ultra-rapid metabolizer patients were detected in relatively high frequencies, CYP2C19 polymorphisms should be taken into account for efficiency and possible clopidogrel related risks in Turkish cardiac patients.