Abstract: Objective　To investigate the correlation between the polymorphism of transcription factor 7-like 2（TCF7L2） gene and breast cancer in Chinese Han women.Methods　According to the inclusion criteria,564 women with breast cancer who received treatment in the Fourth Hospital of Hebei Medical University from January 2011 to January 2012 were selected as the breast cancer group.394 healthy women who underwent physical examination at the same period in Bethune International Peace Hospital were selected as the normal control group.The DNAs were extracted from the peripheral blood of subjects.The genotypes of TCF7L2 gene rs7903146 was detected by polymerase chain reaction-ligase detection reaction（PCR-LDR）.The age,body mass index（BMI） and genotype frequency of CC and CT in TCF7L2 gene rs7903146 of patients in two groups were compared,and the correlation between genotype frequency of CC and CT in TCF7L2 gene rs7903146 and clinical index（age and menopausal status at the time of diagnosis） and pathological index 〔estrogen receptor（ER） status,progesterone receptor（PR） status,human epidermal growth factor receptor 2（HER-2） status,P53 status,Ki-67 status,lymph node metastasis,tumor size,histological grade,tumor stage and molecular typing〕 of patients with breast cancer.Results　There was no significant difference in age of patients between the two groups（P>0.05）;BMI in breast cancer group was greater than that in the control group（P<0.001）.The distribution of the TCF7L2 gene rs7903146 genotype in the control group and the breast cancer group were all in line with the Hardy-Weinberg equilibrium（P>0.05）,which indicated that the study sample had group representativeness.Both of the two groups were not detected with TT genotypes.There was no significant difference in the frequencies of CC and CT genotypes in TCF7L2 gene rs7903146 between the two groups（P>0.05）.The CT genotype frequency of breast cancer patients aged 50 or over after menopause at the time of diagnosis was higher than that of patients aged under 50 pre-menopause（P<0.05）.There was no significant relationship between CT genotype frequency of ER status,PR state,HER-2 status,P53 status,Ki-67 status,lymph node metastasis,tumor size,histological grade,tumor stage as well as molecular typing in breast cancer patients（P>0.05）.Conclusion　The rs7903146 polymorphism of TCF7L2 gene is unrelated to the risk of breast cancer occurrence,and it is not the risk factor of Chinese Han women developing breast cancer.

Key words: Breast neoplasms, Polymorphism,inheritance, Transcription factor 7-like 2 gene, Han nationality

摘要： 目的　探讨核转录因子7类似物2（TCF7L2）基因rs7903146多态性与汉族女性乳腺癌的关系。方法　选取2011年1月—2012年1月于河北医科大学第四医院住院治疗且符合纳入标准的女性乳腺癌患者564例作为乳腺癌组，另选取白求恩国际和平医院同期体检健康的女性394例作为正常对照组。取受试者外周血提取DNA，采用聚合酶链式反应-连接酶检测反应（PCR-LDR）法对TCF7L2基因rs7903146位点进行基因分型。比较两组患者年龄、体质指数（BMI）以及TCF7L2基因rs7903146位点CC、CT基因型频率，并分析TCF7L2基因rs7903146位点CC、CT基因型频率与乳腺癌患者临床指标（诊断时年龄、绝经状态）和病理指标〔雌激素受体（ER）状态、孕激素受体（PR）状态、人类表皮生长因子受体2（HER-2）状态、P53状态、Ki-67状态、淋巴结转移情况、肿瘤直径、组织学分级、肿瘤分期、分子分型〕的关系。结果　两组患者年龄比较，差异无统计学意义（P>0.05）；乳腺癌组BMI大于对照组（P<0.001）。对照组和乳腺癌组TCF7L2基因rs7903146位点基因型分布均符合Hardy-Weinberg平衡（P>0.05），表明研究样本具有群体代表性。两组均未检测出TT基因型,两组TCF7L2基因rs7903146位点CC、CT基因型频率比较，差异无统计学意义（P>0.05）。诊断时年龄≥50岁、绝经后的乳腺癌患者CT基因型频率高于诊断时年龄<50岁、绝经前的乳腺癌患者（P<0.05）。ER状态、PR状态、HER-2状态、P53状态、Ki-67状态、淋巴结转移情况、肿瘤直径、组织学分级、肿瘤分期及分子分型与乳腺癌患者CT基因型频率无关，差异无统计学意义（P>0.05）。结论　TCF7L2基因rs7903146多态性与乳腺癌的发生风险无关，其不是中国汉族女性乳腺癌的患病风险因子。

关键词: 乳腺肿瘤, 多态现象, 遗传, 核转录因子7类似物2基因, 汉族