We did not detect significant associations between DDAH 2 −449C/G polymorphism and risk of CAD in genetic models for GG vs. CC (OR = 0.796, 95% CI: 0.522–1.215), GG vs. GC (OR = 0.979, 95% CI: 0.711–1.348), dominant genetic model (OR = 0.925, 95% CI: 0.68–1.248), and recessive genetic model (OR = 0.806, 95% CI: 0.550–1.182). The gene discussed is DDAH2; the disease is coronary artery disorder.