It has been proved that polymorphisms of DNA repair genes, such as the polymorphisms of XPA ‐4G>A (rs1800975), ERCC2 862G>A (rs1799793) 12, MSH3 3133G>A (rs26279), and PMS1 639G>A (rs5742938) 13, are associated with the risk of lung cancer. The gene discussed is MSH3; the disease is lung cancer.