Polymorphisms of the GSTM1 and CYP2D6 genes associated with susceptibility to lung cancer in Chinese

The case-control study was conducted to examine the association between GSTM1 null and CYP2D6Ch (T₁₈₈/T) genotypes and lung cancer risk among Chinese of Han nationality living in Guangdong. All 191 subjects were investigated with unitary questionnaire and their DNAs were isolated from peripheral lymphocytes by standard procedures with proteinase K digestion and phenol/chloroform extraction. GSTM1(-) was detected with polymerase chain reaction (PCR) in all 191 subjects, involving 59 lung cancer cases, 59 hospital controls and 73 healthy controls. The frequencies of GSTM1(-) were not significantly different between the cases and the two controls overall. However, among adenocarcinoma of lung, the frequency of GSTM1(-) (76.9%) appeared to be higher than that in controls (49.2%), and the odd radios were 3.42-3.45. The results suggested an elevated risk for adenocarcinoma of lung would be shown by GSTM1(-). Using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) to detect CYP2D6 T₁₈₈/T genotype in 59 lung cancer patients and 59 hospital controls, it showed no significant difference between the two groups. However, non-smokers with non-T₁₈₈/T (C₁₈₈/C or C₁₈₈/T) genotype showed 3.78-folds increased risk of lung cancer compared with those with T₁₈₈/T genotype (P=0.036). The data did not suggest a substantial interaction effect between GSTM1 and CYP2D6 polymorphisms and the risk of lung cancer. Additionally, among Chinese (Han) of Guangdong, the frequency of CYP2D6 T₁₈₈ allele appeared to be 57.2%, and GSTM1(-) to be 51.8%. Copyright (C) 1999 Elsevier Science B.V.