Prevalence and types of genetic polymorphisms of CYP2C19 and their effects on platelet aggregation inhibition by...

Area of Science:

• Pharmacogenomics
• Cardiovascular Medicine
• Clinical Chemistry

Background:

• Clopidogrel is a widely used antiplatelet medication crucial for preventing cardiovascular events.
• Individual responses to clopidogrel vary significantly, impacting its clinical efficacy.
• Genetic factors, particularly polymorphisms in the CYP2C19 enzyme, are known to influence clopidogrel metabolism and efficacy.

Purpose of the Study:

• To investigate the distribution of CYP2C19 gene polymorphisms in an Iraqi patient cohort.
• To assess the correlation between CYP2C19 genetic variations and clopidogrel efficacy.
• To evaluate the utility of the vasodilator-stimulated phosphoprotein (VASP) index in measuring clopidogrel response variability.

Main Methods:

• A prospective study involving 100 high-risk cardiovascular patients receiving clopidogrel.
• Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was employed to identify CYP2C19 mutations.
• Dual-color flow cytometry was used to analyze the VASP index at baseline and after one month of therapy.

Main Results:

• The study identified eight CYP2C19 gene mutations, with CYP2C19*1 being the most prevalent allele.
• CYP2C19*1/*1 genotypes indicated rapid metabolizers, while heterozygous *1 alleles showed intermediate metabolism.
• CYP2C19*2 and CYP2C19*3 alleles, associated with resistance, were found in 28% of patients.
• VASP index analysis demonstrated significant inter-individual variability in platelet inhibition.

Conclusions:

• CYP2C19 genotype analysis, alongside the VASP index, can enhance the prediction of clopidogrel response.
• Personalized antiplatelet therapy based on pharmacogenetic profiles may improve clinical outcomes for cardiovascular event prophylaxis.