BACKGROUNDMost of the researches about lung cancer have focused on the polymorphisms of single gene rather than the cooperation of the genes. The aim of this study is to investigate the correlation of gene polymorphisms of cytochrome P450 2E1 (CYP2E1) Rsa I and cytochrome P450 1A1 (CYP1A1) independently and in combination with the risk of lung cancer.

METHODSA case-control study which included 91 lung cancer cases and 91 hospital-based controls was carried out, and all of them were the Han nationality in Guangzhou district. Blood samples were collected for detecting CYP2E1 Rsa I and CYP1A1 gene polymorphisms by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP).

RESULTSNo significant difference was observed in genotype frequencies of CYP2E1 Rsa I and CYP1A1 Msp I between case and control groups. Odd ratio was 5.48 and 1.51 respectively without significant difference (P > 0.05). Individuals with CYP2E1 Rsa I C1C1 and CYP1A1 m2m2 genotype had 3.00-fold risk of developing lung cancer compared with those who had CYP2E1 Rsa I C1C2 and CYP1A1 m1m1 genotype (P < 0.05, 95% CI 1.03-8.78).

CONCLUSIONSSingle polymorphism of CYP2E1 and CYP1A1 doesn't increase the risk of developing lung cancer, but the combination of two genetic polymorphisms significantly increases the risk of developing lung cancer.