有机氯农药及谷胱甘肽转移酶M1基因多态性与乳腺癌关系的研究

Organochlorines, Glutathione S-transferase M1 Genetic Polymorphisms and Risk of Breast Cancer

目的研究血清中有机氯农药水平及谷胱甘肽转移酶M1(GSTM1)基因多态性对女性乳腺癌患病风险的交互作用。方法自2006年9月至2007年10月,在唐山市5所二甲以上医院收集经病理学确诊的乳腺癌患者70例。选取病例所在医院同期住院的女性患者,年龄相差不超过2岁,按相近居住地区进行1∶1配比作为对照。采用气相色谱-电子捕获(GC-ECD)方法检测血清中有机氯农药[滴滴涕(DDT)包括4种同分异构体:p,p'-DDE、p,p'-DDT、o,p'-DDT、p,p'-DDD;六六六(HCH)包括4种同分异构体:α-HCH、β-HCH、γ-HCH、δ-HCH]残留水平,采用聚合酶链反应(PCR)检测GSTM1基因多态性,根据交互作用系数(γ)判断交互作用存在与否以及不同的基因-环境作用类型。结果GSTM1基因多态性与DDT及HCH间存在一定的交互作用,交互作用系数分别为1.237、1.379,交互作用分别表现为次相乘模型和超相乘模型。结论乳腺癌的发生是环境和遗传因素综合作用的结果。GSTM1基因多态性与环境危险因素DDT、HCH的暴露在乳腺癌发生中存在一定的交互作用。

Objective To study the potential effect of gene-environment interaction between glutathione S-transferase M1 （GSTM1） and Serum organochlorines residues on the risk of breast cancer in women, in China. Methods Seventy newly pathologically diagnosed female patients with breast cancer from September 2006 to October 2007 were selected as the cases from five large hospitals in Tangshan. The controls were identified at the same hospital as cases. 1：1 matched case-control study. Between the cases and controls, the difference of age was not over two years and the residence was similar. The organochlorine residues levels in the serum were measured by gas chromatography （GC）. Genotypes of GSTM1 polymorphisms were analyzed by multiplex allele-specific polymerase chain reaction （PCR）. Interaction indexes （γ） were calculated to determine the type of gene-environment interaction. Results After confounding factors adjusted, the result showed that interaction existed in genetic polymorphisms of GSTM1 and DDT, HCH residues, and interaction indexes （γ） value were 1.237 and 1.379. Conclusion GSTM1 genetic polymorphisms and DDT, HCH may present an interaction in the development of breast cancer.