Despite conflicting results, considerable evidence suggests the association between single nucleotide polymorphisms in MTHFR, XRCC1 and OGG1 genes and, risk of developing breast cancer. Here a case-control study is reported, including 135 breat cancer patients and 112 healthy women, all representative of Northern Sardinian population. Polymerase chain reaction/restriction fragment length polymorphism method was used to determine the genotypes of five polymorphisms: MTHFR C677T (rs1801133) and A1298C (rs1801131), XRCC1 Arg194Trp (rs1799782) and Arg399Gln (rs25487) and OGG1 Ser326Cys (rs1052133). Allelic, genotypic and haplotype association analyses with disease risk and clinicopathological parameters were performed. A nominally significant association with breast cancer risk was observed for MTHFR C677T polymorphism heterozygous genotype in the codominant model (OR: 0.57, 95% CI: 0.32–1.00, p = 0.049) and for Cys/Cys genotype of the OGG1 Ser326Cys polymorphism in the recessive model (OR: 0.23, 95% CI: 0.05–1.11, p = 0.0465). No significant differences were found at genotype-level for A1298C polymorphism of the MTHFR gene and Arg194Trp and Arg399Gln of the XRCC1 gene. Furthermore, the OGG1 and XRCC1 rs25487 polymorphisms were nominally associated with PgR, Her2 status and with sporadic breast cancer, respectively. Based on genetic characteristics of individuals included in this study, results suggest that MTHFR CT and OGG1 Cys/Cys genotypes have a protective effect that may have an influence on breast cancer risk in a representative Northern Sardinian population.

中文翻译：

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乳腺癌中MTHFR，XRCC1和OGG1基因多态性：来自北撒丁岛人群的病例对照研究

尽管结果矛盾，但大量证据表明，MTHFR，XRCC1和OGG1基因中的单核苷酸多态性与罹患乳腺癌的风险之间存在关联。在此报道了一项病例对照研究，包括135名乳腺癌患者和112名健康女性，全部代表了北撒丁岛的人口。聚合酶链反应/限制性片段长度多态性方法用于确定5个多态性的基因型：MTHFR C677T（rs1801133）和A1298C（rs1801131），XRCC1 Arg194Trp（rs1799782）和Arg399Gln（rs25487）和OGG1 Ser326Cys（rs1052133）。进行了具有疾病风险和临床病理参数的等位基因，基因型和单倍型关联分析。在共显性模型中观察到MTHFR C677T多态性杂合基因型（OR：0.57，95％CI：0.32–1.00，p = 0.049）和OGG1 Ser326Cys多态性的Cys / Cys基因型与乳腺癌风险存在名义上的显着关联。隐性模型（OR：0.23，95％CI：0.05-1.11，p = 0.0465）。在MTHFR基因的A1298C多态性和XRCC1基因的Arg194Trp和Arg399Gln的基因型水平上没有发现显着差异。此外，OGG1和XRCC1 rs25487多态性在名义上分别与PgR，Her2状态和散发性乳腺癌相关。根据这项研究中个体的遗传特征，