内蒙古地区蒙汉族散发性乳腺癌与BRCA1基因多态性的相关性

Correlation anslysis of sporadic breast cancer and BRCA1 gene plymorphisms in the Han Nationality and the Mongol Nationality of Inner Mongolia Region

目的探讨内蒙古地区蒙汉族散发性乳腺癌与BRCA1基因多态性，尤以2731位点（rs799917）为重的相关性。方法采用前瞻性研究方法，选择103例散发性乳腺癌患者（病例组）及103例健康体检人群（对照组）作为研究对象，应用PCR及直接测序法分析我区散发性乳腺癌与BRCA1基因2731位点多态性的相关性。结果病例组两民族样本在年龄分层、病理分级、免疫组化情况、淋巴结转移中的分布差异无统计学意义（P〉0.05），对照组在年龄分层中差异亦无统计学意义（P〉0.05），病例组及对照组在年龄分层中差异无统计学意义（P〉0.05）；在内蒙古地区，不论是蒙古族还是汉族，BRCA1基因2731位点均可检出3种基因型：即CC、CT及TT型。病例组此3种基因型频率分别为：13.1%（8/61）、26.2%（16/61）、60.7%（37/61）（汉族）和16.7%（7/42）、28.6%（12/42）、54.7%（23/42）（蒙古族），T等位基因频率为71.8%（74/103），C等位基因频率为28.2%（29/103）；对照组3种基因型分别为：18.0%、31.1%、50.9%（汉族）和23.8%、38.1%、38.1%（蒙古族），T等位基因频率为62.9%，C等位基因频率为37.1%。关于BRCA1 2731位点基因多态性两组相比无统计学差异（χ^2＝3.438，P＝0.752）；病例组中T等位基因分布频率显著增高（χ^2＝4.185，P＝0.041）。结论BRCA1基因2731位点与内蒙古地区蒙汉族散发性乳腺癌无明显相关，但BRCA1 2731位点C等位基因可能是该地区蒙汉族患散发性乳腺癌的保护基因之一。

ObjectiveTo study the correlationship between the BRCA1 gene polymorphisms, especially in 2731 loci （rs799917）, and sporadic breast cancer in the Han nationality and the Mongol nationality of the Inner Mongolia region.MethodsUsing the prospective study method, 103 cases of patients with sporadic breast cancer （case group） and 103 cases of normal physical examination people （control group） were enrolled. PCR and direct sequencing method were used for analyzing the correlationship of 2731 loci polymorphisms of BRCA1 and sporadic breast cancer in our zone.ResultsIn the case group, the age stratification, pathologic stage, immunohistochemistry and the distribution of lymph node metastasis had no significant difference in two ethnic group （P〉 0.05）. The age stratification of control group also had no significant difference in two ethnic group （P〉0. 05）. There was no statistically significant difference in age stratification of the case group and the control group （P〉0.05）. In the Inner Mongolia region, BRCA1 gene 2731 loci genotypes check out three genotypes： namely TT, CT and CC. The frequencies of genotype TT, CT, CC in the case group were 13.1%, 26.2%, 60.7% （ the Han nationality） and 16.7%, 28.6%, 54.7% （the Mongol nationality）, respectively. Meanwhile the frequencies of allele T and allele C were 71.8% and 28.2%. In the control group, the frequencies of genotype TT, CT, CC were 18.0%, 31.1%, 50.9% （ the Han nationality） and 23.8%, 38.1%, 38.1% （ the Mongol nationality）, respectively, and the frequencies of allele T and allele C were 62.9% and 37.1%. BRCA1 gene 2 731 loci gene polymorphism had no significant difference in two groups （χ^2=3.438, P=0.752）, but T allele frequency distribution in the case group was significantly increased （χ^2=4.185, P=0.041）.ConclusionThere is no obvious correlation between the BRCA1 gene 2731 loci and sporadic breast cancer in the Han nationality and the Mongol nationality of the Inner Mongolia region. C allele of BRCA1 gene 2731 loci may be one of the protective gene of sporadic breast cancer.