Regarding the association between genetic polymorphisms of GSTM1 and smoking-related CAD, smokers with the GSTM1 null genotype have a greater risk of CAD compared with non-smokers with the GSTM1-positive genotype [odds ratio (OR), 2.07; 95% confidence interval (CI), 1.06–4.07]. This evidence concerns the gene GSTM1 and coronary artery disorder.