目的 通过对肺癌组及对照组细胞色素P450 2C19（cytochrome P450 2C19，CYP2C19）等位基因进行基因分型，探讨CYP2C19基因中G681A和G636A多态性的分布与肺癌易感性的关系。方法 提取293例肺癌患者和300例健康对照组患者的外周血基因组DNA，用实时荧光PCR方法对CYP2C19进行基因分型。对肺癌组和健康对照组基因分布进行比较。结果 肺癌组CYP2C19*2/*3基因型显著高于正常对照组，差异有统计学意义（18.77% vs 5.67%；P=0.000），对照组CYP2C19*1/*2基因型显著高于肺癌组，差异有统计学意义（30.67% vs 13.99%；P＝0.000）。两组病例CYP2C19代谢型分布比较结果，肺癌组慢代谢型频率超过对照组一倍以上（33.45% vs 15.33%）。肺癌与各相关指标的多因素Logistic相关分析结果显示，CYP2C19慢代谢型可能是肺癌发生的独立危险因素(P=0.000，OR:2.755,95%CI: 1.748～4.343)。结论 CYP2C19慢代谢型可能与肺癌的发生有关。

Objective To investigate the correlation between the distribution of G681A and G636A polymorphisms in CYP2C19 gene and the risk of lung cancer. Methods The peripheral blood DNA was extracted from 293 patients with lung cancer and 300 healthy controls. The genotyping was conducted by using the real-time fluorescent polymerase chain reaction. Both the genotype and allele distributions were compared in patients with lung cancer and healthy controls. Results The CYP2C19*2/*3 genotype in the lung cancer group was significantly higher than those in the controls （18.77% vs 5.67%；P=0.000）. The CYP2C19*1/*2 genotype in the healthy control was significantly higher than those in lung cancer group (30.67% vs 13.99%；P＝0.000). The frequencies of weak metabolic gene of CYP2C19 were more than one times in the controls （33.45% vs 15.33%）. Multivariate logistic regression analysis showed that the poor metabolizer gene of CYP2C19 may be an independent risk factor for lung cancer (P=0.000，OR:2.755, 95%CI: 1.748～4.343). Conclusion The poor metabolizer gene of CYP2C19 might be related to the occurrence of lung cancer.