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Published on: April 1, 2019
Prevalence of CYP2C19 polymorphisms in the Lebanese population
Isabelle Djaffar Jureidini1, Nabil Chamseddine, Sose Keleshian
1Department of Clinical Laboratory, Saint George Hospital University Medical Center, Achrafieh Beirut 1100, 2807 Beirut, Lebanon. idjureidini@stgeorgehospital.org
Molecular Biology Reports
|March 8, 2011
Summary
Genetic variations in the CYP2C19 enzyme affect clopidogrel metabolism. This study determined CYP2C19 variant frequencies in Lebanon, finding them similar to Caucasian populations, suggesting FDA guidelines for personalized antiplatelet therapy are applicable.
Area of Science:
- Pharmacogenomics
- Cardiovascular Medicine
- Clinical Chemistry
Background:
- Clopidogrel, combined with aspirin, is a standard oral antiplatelet therapy for preventing ischemic events post-coronary syndromes or stent placement.
- Genetic polymorphisms in cytochrome P450 2C19 (CYP2C19) significantly influence clopidogrel metabolism, affecting patient response and cardiovascular outcomes.
- Individuals with CYP2C19 variants (e.g., *2, *3) exhibit reduced clopidogrel metabolism, increasing risks of cardiovascular events and stent thrombosis compared to those with the wild-type (*1) allele.
Purpose of the Study:
- To investigate the prevalence of CYP2C19 genetic variants (*1, *2, *3) within the Lebanese population.
- To assess the applicability of current FDA recommendations for genotype-guided clopidogrel therapy in Lebanon.
- To identify potential genetic risk factors for atherothrombotic events in Lebanese individuals undergoing antiplatelet therapy.
Main Methods:
- Genotyping of CYP2C19 variants (*1, *2, *3) was performed using Polymerase Chain Reaction-Restriction Length Polymorphism (PCR-RFLP) assays.
- A cohort of 161 unrelated, healthy Lebanese volunteers was analyzed to determine allele frequencies.
- Statistical comparison of allele frequencies with existing data from Caucasian populations was conducted.
Main Results:
- The allele frequencies for CYP2C19*2 and CYP2C19*3 in the Lebanese sample were 0.13 and 0.03, respectively.
- Approximately 24.2% of the Lebanese subjects were identified as carriers of the CYP2C19*2 or *3 variants.
- The observed frequencies of CYP2C19 allelic variants in Lebanon showed no significant difference compared to Caucasian populations.
Conclusions:
- The prevalence of CYP2C19 genetic variants in Lebanon is comparable to that in Caucasian populations.
- Implementing FDA recommendations for CYP2C19 genotyping can help identify Lebanese patients at higher risk for atherothrombotic events.
- Personalized antiplatelet therapy, considering CYP2C19 genotype, can optimize treatment strategies and improve outcomes for Lebanese patients.
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