Therapy with clopidogrel and aspirin, commonly known as dual antiplatelet therapy, is a widely adapted secondary prevention strategy among coronary artery disease patients treated with percutaneous coronary intervention. However, in addition to response variability and high on-treatment platelet reactivity and their relation to increased adverse events during clopidogrel therapy, candidate gene studies and genome-wide association studies have highlighted the significance of single nucleotide polymorphisms of genes associated with clopidogrel metabolism in coronary artery disease patients. Genotyping may have an emerging role in personalized antiplatelet therapy, particularly with the advent of new P2Y₁₂ receptor blockers that have more rapid and potent pharmacodynamic properties than clopidogrel. The current review discusses the role of genotyping in personalizing P2Y₁₂ receptor-blocker therapy.