Clinical studies also showed there is a direct correlation between increased levels of proinflammatory cytokines (IFN-γ, TNFα, IL-2, IL-6, IL-9, and IL-17) and anti-inflammatory cytokines (IL-4 and IL10) with the severity of CAD determined by coronary angiography [25, 26]. This evidence concerns the gene IL2 and coronary artery disorder.