摘要目的:分析共济失调毛细血管扩张突变基因(ATM)rs1801516、rs1800054两位点单核苷酸多态性(SNP)与蒙古地区散发性乳腺癌(SBC)的相关性。方法:前瞻性收集2018年1月至2019年9月在内蒙古医科大学附属医院就诊的SBC患者102例(汉族72例、蒙古族30例)作为病例组，并选取同期健康体检女性102例(汉族72例、蒙古族30例)作为对照组，采集受试者静脉血2 ml提取细胞核脱氧核糖核酸(DNA)，根据单核苷酸多态性数据库(dbSNP)数据库选取出ATM基因高度多态性rs1801516和rs1800054位点，采用聚合酶链式反应(PCR)及直接测序法检测两位点多态性，分析两位点单核苷酸多态性与内蒙古地区SBC易感的相关性，并分析内蒙古地区SBC患者临床病理因素与ATM基因多态性的关系。结果:ATM基因rs1801516位点检出野生纯合子GG、突变杂合子GA及突变纯合子AA型，rs1800054位点仅检出野生纯合子CC型。各基因型频率及等位基因频率在蒙古族乳腺癌组与汉族乳腺癌组、蒙古族对照组与汉族对照组、蒙古族乳腺癌组与蒙古族对照组、汉族乳腺癌组与汉族对照组中分布差异均无统计学意义(均 P>0.05)。Logistic回归分析显示，等位基因G是内蒙古地区SBC的易感基因( OR：1.775，95% CI：1.04~3.03， P＝0.04)。ATM rs1801516多态性与乳腺癌肿瘤长径≤2 cm和(或)不伴有淋巴结转移的患者乳腺癌患病风险增加有关(均 P<0.05)。 结论:ATM基因rs1801516和rs1800054位点基因多态性可能与内蒙古地区SBC患病风险无明显相关性。rs1801516位点可能与乳腺癌肿瘤长径≤2 cm和(或)不伴有淋巴结转移的患者乳腺癌患病风险增加存在相关性，基因G可能是内蒙古地区SBC的易感基因之一。

abstractsObjective:To analyze the relationship between ataxia telangiectasia mutated (ATM) single nucleotide polymorphism (SNP) at rs1801516 and rs1800054 and sporadic breast cancer (SBC) in Inner Mongolia.Methods:A total of 102 patients with SBC (72 Han and 30 Mongolian) who were admitted to the Affiliated Hospital of Inner Mongolia Medical University from January 2018 to September 2019 were prospectively collected as case group and 102 healthy women (72 Han and 30 Mongolian) during the same period as control group. 2 ml of venous blood was collected to extract DNA. According to the Single Nucleotide Polymorphism Database (dbSNP), the highly polymorphic sites rs1801516 and rs1800054 of ATM gene were selected. The polymerase chain reaction (PCR) and direct sequencing were used to detect the polymorphism of the two sites, and the correlation between the single nucleotide polymorphism of the two sites and the susceptibility of SBC in Inner Mongolia was analyzed. The potential association between clinicopathological factors and ATM gene polymorphism in patients with SBC in Inner Mongolia were explored.Results:GG, GA and AA genotypes were detected in rs1801516 locus of ATM gene. Only CC genotype was detected in the rs1800054 locus of ATM gene. There was no significant difference in the distribution of genotype frequency and allele frequency between Mongolian breast cancer group and Han breast cancer group, Mongolian control group and Han control group, Mongolian breast cancer group and Mongolian control group, Han breast cancer group and Han control group (all P>0.05). Logistic regression analysis showed that allele G was the susceptibility gene of SBC in Inner Mongolia ( OR: 1.775, 95% CI: 1.04-3.03, P=0.04). ATM rs1801516 polymorphism may be associated with increased risk of breast cancer in patients with mass diameter ≤2 cm and/or without lymph node metastasis (all P<0.05). Conclusions:The polymorphism of ATM gene rs1801516 and rs1800054 may not be significantly correlated with the risk of SBC in Inner Mongolia. The rs1801516 locus may be associated with increased risk of breast cancer in patients with mass diameter ≤2 cm and/or without lymph node metastasis. Gene G may be one of the susceptible genes of SBC in Inner Mongolia.