ABSTRACT
<p><b>OBJECTIVE</b>To study the correlation of polymorphisms of CYP1A1 MSPI and glutathiones S-transferase (GST-M1) independently and in combination with the risk of lung cancer.</p><p><b>METHODS</b>A case control study which included 91 cases of lung cancer and 138 controls collected from the First Affiliated Hospital of Sun Yat-sen University of Medical Sciences, Guangzhou Tumor Hospital and The Red Cross Hospital of Guangzhou or conmunity area. All subjects were investigated with a uniform questionnaire. Blood samples were collected from all cases and controls for detecting CYP1A1 MSPI and GST-M1 polymorphisms which were analyzed by PCR and RFLP.</p><p><b>RESULTS</b>It showed that there was no significant difference in frequencies of this genotypes of CYP1A1 MSPI between the two groups. The frequency of GST-M1 null (0/0) genotype was higher in the case group than in the control group, with an OR of 1.38 (95% CI 0.81 - 2.38), but there was no statistical significance. However, combination of several genotypes was strongly associated with lung cancer. There was a synergistic interaction between the m2m2 genotype of CYP1A1 MSPI and GST-M1 (0/0) genotype, with an OR of 2.47 (95% CI 1.03 - 5.90).</p><p><b>CONCLUSION</b>The combination of two genetic polymorphisms significantly increases the risk of lung cancer.</p>