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  • Poster presentation
  • Open Access

The impact of CYP2C19 *2 and *3 polymorphism on clopidogrel response following coronary stenting in Saudi patients with acute coronary syndrome

BMC Genomics201415 (Suppl 2) :P26

  • Published:


  • Acute Coronary Syndrome
  • Clopidogrel
  • Antiplatelet Agent
  • Drug Elute Stent
  • Platelet Inhibition


Clopidogrel is a widely used oral, antiplatelet agent of thienopyridine class used to inhibit thrombosis following drug eluting stent (DES) placement [1]. The variability of response (platelet function testing) to clopidogrel is multifactorial and genetic polymorphism has been known to be the main cause [2].

Materials and methods

Ninety Saudi patients with acute coronary syndrome who underwent coronary angioplasty with drug eluting stents were consecutively enrolled in Prince Sultan Cardiac Center, Buraidah. Patients received clopidogrel as per usual dose of 300mg loading (about 4 days prior to procedure) and 75mg per day as maintenance dose. Two blood samples were withdrawn from each patient. DNA was extracted by [MagNAPure LC,Roche, Germany]. CYP2C19 and Genotyping for *1, *2 and *3 was conducted by real-time PCR [Roche Molecular Biochemicals, Mannheim, Germany]. Platelet function testing was carried out using (Verify Now P2Y12) and all the in-hospital clinical events were monitored for patients.


Sixty (66.7%) patients have the genotype 1/1, 28 (31.1%) patients have 2/2 and 2 (2.2%) have1/2 genotype. There was no significant difference in mean P2Y12 reaction units (PRU) of patients with wild variant and resistant variant (193±76u vs.212± 55.4 p value=0.349). The mean percentage of inhibition also did not differ significantly in the two groups (16.9±15.5 for wild variant and 9.4 for resistant variant P value= 0.135). One in-hospital clinical event (in-stent thrombosis) was encountered and thus was too rare for any significant comparison.


In this study genotyping revealed polymorphism but we found no impact of the polymorphism on the percentage of platelet inhibition following four days of clopidogrel ingestion.

Authors’ Affiliations

Intervention group at Prince Sultan Cardiac Center, Qassim & Genetic laboratory at Qassim University, Kingdom of Saudi Arabia
Prince Sultan Cardiac Centre, Buraidah, Qassim, Kingdom of Saudi Arabia


  1. Mehta SR, Yusuf S, Peters RJ, et al: Effects of pretreatment with clopidogrel and aspirin followed by long-term therapy in patients undergoingpercutaneous coronary intervention: the PCI-CURE study. Lancet. 2001, 358: 527-533.View ArticlePubMedGoogle Scholar
  2. Mega JL, Close SL, Wiviott SD, et al: Cytochrome P-450 polymorphisms and response to clopidogrel. N Engl J Med. 2009, 360: 354-362.View ArticlePubMedGoogle Scholar


© Khalaf et al; licensee BioMed Central Ltd. 2014

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.