Combined frequencies of GSTM1 and GSTT1 polymorphisms Wild/Wild, Wild/Null, Null/Wild and Null/Null in healthy control were 66.80, 10.40, 23.60 and 1.6 %, respectively, whereas in NSCLC patients the frequencies were 59.34, 14.63, 21.95 and 4.06 %, respectively. The gene discussed is GSTM1; the disease is non-small cell lung carcinoma.