Abstract 2379: Evaluation Of The Effect Of The PlA1/A2 Dimorphism, Of The P2Y1 Receptor Gene 1622A/G Mutation And Of The COX-1 Gene 22C/T Mutation On Platelet Response To Aspirin
Background: The antiplatelet drug aspirin is widely used to prevent acute ischemic events. However, platelet response to aspirin is highly variable, which may be partly explained by genetic variability affecting platelet enzymes or receptors.
Objective: To evaluate the impact of the dimorphism on the β3 allele of the α2bβ3 integrin (PlA1/A2), of the P2Y1 receptor gene mutation (1622A/G) and of the COX-1 gene mutation (22C/T) on platelet response to aspirin.
Method: One hundred and ninety-two stable CAD patients under daily aspirin therapy were recruited. Platelet aggregation was measured by light transmission aggregometry (LTA) with arachidonic acid at 1.6 mM as the agonist. Genotyping was performed by standard PCR method.
Results: The genotype frequency of PlA1A1:PlA1A2:PlA2A2 was 72.8%:25.6%:1.6%. The genotype frequency AA:AG:GG of the P2Y1 receptor gene at the 1622 position was 70.7%:25.5%:3.6%. The genotype frequency CC:CT:TT of the COX-1 gene at the 20 position was 84.9%:14.6%:0.5%. Mean platelet aggregation (%) was: Aspirin resistance, defined as LTA > 20%, was associated with the 1622A/G polymorphism of the P2Y1 receptor gene (p=0.002); neither PlA1/A2 nor the polymorphism of the COX-1 gene was linked to aspirin resistance (p=0.933 and p=0.476, respectively).
Conclusion: In our population, the mutation affecting the P2Y1 receptor gene was linked to aspirin resistance.