目的观察三阴性乳腺癌（TNBC）CHEK2 基因功能区单核苷酸多态性（SNP）位点的突变情况。方法选取40例2017年 12月至2020年1月在贵航贵阳医院和贵州中医药大学第一附属医院门诊及住院的TNBC患者的病理组织蜡片，选取对TNBC相 关性较大的CHEK2 基因上的24个SNP位点进行检测，运用石蜡DNA抽提试剂盒提取病理组织蜡片的DNA后进行甲基化处理。 使用引物设计软件PyroMark Assay Design 2.0设计引物序列，经聚合酶链反应扩增后通过焦磷酸测序检测法检测其CHEK2 基因 功能区候选SNP位点，并分析其SNP位点的突变情况，最后使用焦磷酸测序仪自带的Pyro Q‐AQ软件自动分析每个位点碱基比 例。结果对40例TNBC患者的CHEK2 基因上24个SNP位点进行检测，其中D82A和E79G位点序列有重复结构，设计不到合格 引物，未予检测。结果发现突变频率及样本量位于前4位的分别是K131N、K142E、P152S和T366FS位点。其中K131N、K142E和 P152S属于叉头相关区域，而T366FS属于激酶区。未检测到突变的位点是T59K、I157T、1100delC、E394K、Y424C、R475FS。R145W 位点大部分样品无突变，小部分样品有明显突变，其余位点突变率较低。结论TNBC患者的CHEK2 基因位点突变频率较高的4 个位点为K131N、K142E、P152S和T366FS。

Objective To observe the mutation of single nucleotide polymorphism (SNP) in the functional region of CHEK2 gene in triple⁃negative breast cancer (TNBC). Method We Collected wax slices of pathological tissues of 40 TNBC patients who were diagnosed in Guihang Guiyang Hospital and The First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine from December 2017 to January 2020, and then selected 24 sites on the CHEK2 gene, which is more related to TNBC, and used paraffin DNA extraction. The extraction kit extracts DNA from wax slices of pathological tissues and then undergoes methylation treatment. Use the primer design software PyroMark Assay Design 2.0 to design the primer sequence. After polymerase chain reaction amplification, the candidate SNP sites of the CHEK2 gene functional region are detected by pyrosequencing detection method, and the mutations of the SNP sites are analyzed. Finally, the pyrosequencer comes with the Pyro Q⁃AQ software automatically analyzes the base ratio of each site. Result The 24 SNP sites on the CHEK2 gene of 40 TNBC patients were detected. Among them, D82A and E79G have repeated structures in the sequence, and no qualified primers were designed, so they were not tested. The results showed that the first four mutation frequencies and sample sizes were K131N, K142E, P152S and T366FS, respectively. Among them, K131N, K142E and P152S belong to the fork⁃head related region, while T366FS belongs to the kinase region. The sites where no mutations were detected were T59K, I157T, 1100delC, E394K, Y424C and R475FS.Most samples at R145W site have no mutations, a small number of samples have obvious mutations, and the mutation rate of other sites is low. Conclusion In patients with TNBC, the four loci with higher mutation frequency of CHEK2 gene are K131N, K142E, P152S and T366FS.