XPC 基因 rs2228000（C/T）多态性与乳腺癌易感性的Meta分析

目的：定量探讨着色性干皮病 C 组（XPC）基因 rs2228000（C ／T）多态性与乳腺癌易感性之间的关系。方法通过计算机检索 PubMed、Cochrane Library、中国生物医学文献数据库（CBM）、万方医药期刊全文数据库、中国期刊全文数据库（CNKI）及维普数据库（VIP）,检索时间截至2015年12月,搜集有关 XPC rs2228000（C ／T）位点多态性与乳腺癌风险的病例对照研究。采用 STATA 12．0软件进行结果分析,计算比值比（OR）和95％CI。结果总共纳入8篇文献,包括9个病例对照研究（3850例乳腺癌患者和5047例健康对照）。纯合子模型（TT vs．CC：OR ＝1．28,95％CI 为1．08～1．52,Z ＝2．80, P ＝0．005）和隐性模型（TT vs．TC ＋CC：OR ＝1．23,95％CI 为1．05～1．43,Z ＝2．64,P ＝0．008）中 XPC rs2228000（C ／T）多态性与乳腺癌易感性有关,而等位基因模型、杂合子模型、显性基因模型中 XPC rs2228000（C ／T）位点多态性与乳腺癌风险无关（P ＞0．05）。在亚洲人群和 PCR-RFLP 亚组的4种基因模型中,XPC rs2228000（C ／T）多态性与乳腺癌易感性有关（T vs．C：OR ＝1．21,95％CI 为1．05～1．40, Z ＝2．63,P ＝0．009;TT vs．CC：OR ＝1．55,95％CI 为1．13～2．13,Z ＝2．70,P ＝0．007;TT ＋TC vs．CC：OR ＝1．26,95％CI 为1．02～1．55,Z ＝2．19,P ＝0．028;TT vs．TC ＋CC：OR ＝1．39,95％CI 为1．04～1．87, Z ＝2．23,P ＝0．026）。基于对照组来源的亚组分析,社区来源的纯合子模型中 XPC rs2228000（C ／T）多态性与乳腺癌发病风险有关（TT vs．CC：OR ＝1．27,95％CI 为1．02～1．57,Z ＝2．16,P ＝0．031）。结论XPC rs2228000（C ／T）多态性可能与乳腺癌风险有关,尤其在亚洲人群中,基因型 TT 可能增加乳腺癌发病风险。     

2q35 rs13387042和8q24 rs13281615单核苷酸多态性与中国东北汉族绝经前妇女乳腺癌风险关系

背景与目的：乳腺癌作为中国女性最常见的恶性肿瘤,每年的新发数量和死亡数量分别占全世界的12.2%和9.6%,但与中国乳腺癌患者明显相关的基因多态位点至今尚不清楚。本研究旨在探讨2q35 rs13387042和8q24 rs13281615单核苷酸多态性与中国北方汉族绝经前妇女乳腺癌风险关系,为预防和治疗乳腺癌提供循证依据。方法：采用多重单碱基延伸单核苷酸多态性分型技术(SNaPshot)分析方法,检测了280例绝经前乳腺癌患者和287例绝经前正常对照者2q35 rs13387042和8q24 rs13281615多态性位点基因型,并比较不同基因型和等位基因与乳腺癌风险的关系。结果：2q35 rs13387042多态性位点基因型频率在乳腺癌和对照样本之间差异有统计学意义(P=0.017);8q24 rs13281615多态性位点基因型频率在乳腺癌和对照样本之间差异无统计学意义(P=0.967)。Logistic回归分析结果显示,对于2q35 rs13387042位点,与GG相比,GA和GA+AA基因型携带者显著增加乳腺癌的患病风险(OR=1.793,95%CI：1.177～2.733,P=0.007;OR=1.691,95%CI：1.122～2.550,P=0.012),而AA携带者与乳腺癌的患病风险无关(OR=0.572,95%CI：0.104～3.153,P=0.521);与G等位基因相比,A等位基因显著增加乳腺癌的患病风险(OR=1.505,95%CI：1.033～2.193,P=0.033)。对于8q24rs13281615位点,与AA相比,AG、GG和AG+GG基因型携带者与乳腺癌的患病风险无关(OR=0.992,95%CI：0.660～1.490,P=0.968;OR=1.047,95%CI：0.642～1.708,P=0.853;OR=1.007,95%CI：0.682～1.487,P=0.971);与A等位基因相比,G等位基因不增加乳腺癌患病风险(OR=1.021,95%CI：0.809～1.288,P=0.863)。结论：本实验证实2q35 rs13387042多态性位点能够增加中国北方汉族绝经前妇女乳腺癌易感风险,而8q24 rs13281615多态性位点与中国北方汉族绝经前妇女乳腺癌易感性无明显相关性。     

TOX3基因单核苷酸多态与中国北方汉族绝经前妇女乳腺癌风险关联的研究

目的:探讨TOX3基因单核苷酸多态与中国北方汉族绝经前妇女乳腺癌风险的关系。方法:采用多重单碱基延伸单核苷酸多态性分型技术(Snapshot)分析方法,检测280例绝经前的乳腺癌患者和287例绝经前的正常对照者TOX3基因rs3803662和rs12443621多态性位点基因型,并比较不同基因型与乳腺癌风险的关系。结果:TOX3基因rs3803662和rs12443621多态性位点基因型频率,在乳腺癌病例组和对照组之间差异无统计学意义,P值分别为0.718和0.340。Logistic回归分析结果显示,对于rs3803662位点,与GG基因型相比,GA、AA和GA+AA基因型与乳腺癌的危险性无关(OR=0.846,95%CI:0.489～1.463,P=0.549;OR=0.802,95%CI:0.470～1.368,P=0.418;OR=0.821,95%CI:0.492～1.368,P=0.449);对于rs12443621位点,与GG基因型相比,GA、AA和GA+AA基因型与乳腺癌的危险性无关(OR=0.755,95%CI:0.518～1.099,P=0.755;OR=0.850,95%CI:0.528～1.368,P=0.504;OR=0.781,95%CI:0.548～1.112,P=0.170)。结论:在目前样本条件下,TOX3基因rs3803662和rs12443621位点多态性与中国北方汉族绝经前妇女乳腺癌易感性之间无明显关联。     

WT1基因 rs16754位点多态性与急性髓系白血病预后关系的 Meta 分析

目的：采用 Meta 分析总结 WT1基因 rs16754位点多态性与急性髓系白血病（AML）预后的关系。方法以英文检索词“WT1”“polymorphism”“Leukemia,Myeloid,Acute”检索 PubMed 数据库,同时以中文检索词“WT1”“多态性”“急性髓系白血病”检索中国知网、万方数据库和中国生物医学文摘数据库,时限截至2015年12月1日。结果共纳入11篇英文文献,样本量共计2789例。 Meta 分析结果显示, WT1基因 rs16754位点多态性与 AML 患者化疗完全缓解情况无相关性（RR＝1.02,95% CI 0.99～1.06, P＝0.20）,与总体生存（OS）（HR＝0.68,95% CI 0.45～1.02,P＝0.06）、5年 OS（RR＝1.10,95% CI 0.90～1.34,P＝0.37）及无复发生存期（RFS）（HR＝0.80,95% CI 0.54～1.19,P＝0.27）也无相关性。结论 WT1基因 rs16754位点多态性与 AML 预后各指标无相关性。     

Dicer1基因单核苷酸多态性与浙江地区BRCA1/BRCA2阴性家族性乳腺癌的相关性研究

[目的]研究Dicer1基因单核苷酸多态性与浙江地区BRCA1/BRCA2阴性家族性乳腺癌易感性的相关性.[方法]选择3个单核苷酸多态性位点(rs74899136、rs2297730和rs147668333),采用PCR测序方法对65例BRCA1/BRCA2阴性家族性乳腺癌患者和100名健康女性进行分析,x2检验比较两组在等位基因和基因型分布频率上的差异,非条件Logistic回归评价多态性位点与乳腺癌易感性的相关性.[结果]rs2297730的G等位基因和A/G基因型在乳腺癌病例组中的分布频率显著高于对照组(OR=1.873,95％CI:1.174～2.988,P=0.008;OR=3.133,95％CI:1.562～6.287,P=0.004).另外2个多态性位点等位基因和基因型分布频率在两组间无显著差异(P＞0.05).rs2297730在共显性、显性、超显性以及加性遗传模式下与乳腺癌相关(P＜0.05),最佳遗传模式为显性.[结论] Dicer1基因rs2297730与浙江地区BRCA 1/BRCA2阴性家族性乳腺癌易感性相关.     

淋巴细胞弱化因子基因多态性与乳腺癌发病风险研究

目的:探讨B及T淋巴细胞弱化因子(B and T Lymphocyte attenuator,BTLA)SNP位点在黑龙江省妇女乳腺癌患者及正常对照人群中的基因型和等位基因频率;确定BTLA基因与黑龙江省妇女乳腺癌发病风险的相关性.方法:抽取280例乳腺癌患者及262例健康女性外周血5mL,试剂盒提取DNA后.利用聚合酶链式反应限制性片段长度多态性(polymerase chain reaction restriction fragment length polymorphism,PCR-RFLP)技术进行BTLA基因外显子及内含子的SNP位点DNA扩增,检测BTLA基因位点多态性,分析患者与正常对照差别,进而确定该基因与黑龙江省妇女乳腺癌的相关性.结果:乳腺癌患者的BTLA基因外显子及内含子中杂合子基因型高于正常对照者,有统计学差异(P＜0.05,OR>1.00),内含子中rs2705535 GG基因型乳腺癌患者组中的基因频率低于正常对照组(P＜0.05,OR<1.00).A等位基因在乳腺癌患者中频率高于正常对照组(P＜0.05,OR>1.00).具有统计学意义.结论:BT-LA基因多态性与黑龙江省妇女乳腺癌发病风险存在一定关联性.     

CAV-1基因多态性与散发乳腺癌易感性的相关性分析

摘 要：［目的］ 探讨CAV-1基因多态性与散发乳腺癌的相关性。［方法］ 采用病例对照研究，纳入经病理确诊的135例女性乳腺癌患者作为实验组，166例女性健康体检者为对照组。通过竞争性等位基因特异性PCR法对研究对象基因位点进行分型；采用χ2检验比较CAV-1各SNP基因型及等位基因频率在两组中的分布差异；非条件Logistic回归分析CAV-1基因多态性与乳腺癌易感性的关联。［结果］ 在共显性模型、显性模型及等位基因模型下rs3807987及rs7804372位点多态性与乳腺癌易感性密切相关。rs3807987：相对于GG基因型，AG、AA基因携带者（AG/AA基因型）均增加乳腺癌的发病风险（P＜0.05），OR值分别为2.110（95%CI：1.270~3.505）、1.968（95%CI：1.205~3.216）。rs7804372位点：相对于TT基因型，AT、AA基因携带者（AT/AA基因型）均增加乳腺癌的发病风险（P＜0.05），OR值分别为2.088（95%CI：1.285~3.392）、2.059（95%CI：1.293~3.280）。rs12672038位点：在共显性模型、显性模型、等位基因模型均未见rs12672038位点多态性分布与乳腺癌发病风险之间存在相关性。［结论］ CAV-1基因rs3807987与rs7804372多态性与乳腺癌易感性相关。     

云南省汉族人群TNF-α基因多态性与非小细胞肺癌发生、发展的相关性

背景与目的：肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）不仅是一种重要的炎症因子,还与肿瘤的发生、发展密切相关。探讨TNF-α基因多态性与云南省汉族人群非小细胞肺癌（non-small cell lung cancer,NSCLC）发生、发展的相关性。方法：选取云南省425例汉族人群NSCLC病例和438名健康体检者,采用TaqMan探针基因分型法对TNF-α基因启动子区域5个单核苷酸多态性（single nucleotide polymorphism,SNP）位点rs1799964（-1031T>C）、rs1800630（-863C>A）、rs1799724（-857C>T）、rs1800629（-308G>A）和rs361525（-238G>A）进行基因分型并分析其等位基因、基因型及所构建的单倍型在NSCLC病例及健康对照者中的频率差异。结果：TNF-α基因启动子5个SNP位点的等位基因和基因型频率在NSCLC病例组和对照组间差异无统计学意义（P＞0.05）。病例分层分析发现,rs1799724（C>T）的T等位基因在腺癌组中的频率显著高于对照组（P=0.010,OR=1.56,95% CI：1.11~2.19）,在显性模式下携带T等位基因的个体（TT+CT）患肺腺癌的风险显著升高（P=0.007,OR=1.66,95% CI：1.15~2.42）。rs1800630（C>A）的A等位基因在腺鳞癌及其他类型肺癌组中的频率显著高于对照组,差异有统计学意义（P=0.013,OR=2.15,95% CI：1.16~3.96）。单倍型分析结果显示,单倍型rs1799724T-rs1800629G在腺癌组中的频率显著高于对照组（P=0.048,OR=1.42,95% CI：1.00~2.01）。结论：位于TNF-α基因启动子区域的SNP位点rs1799724（C>T）等位基因T和基因型TT可能是云南省汉族人群NSCLC中腺癌发生的风险性因素。SNP位点rs1800630（C>A）等位基因A可能是云南省汉族人群NSCLC中腺鳞癌及其他类型肺癌发生的风险性因素。     

MAP3K1及LSP1基因单核苷酸多态与中国北方汉族绝经前妇女乳腺癌风险相关性

目的:探讨MAP3K1及LSP1基因单核苷酸多态与中国北方汉族绝经前妇女乳腺癌风险的关系。方法:采用多重单碱基延伸单核苷酸多态性分型技术(Snapshot)分析方法,检测280例绝经前乳腺癌患者和287例绝经前正常对照者MAP3K1基因rs889312和LSP1基因rs3817198多态性位点基因型,并比较不同基因型与乳腺癌风险的关系。结果:MAP3K1基因rs889312和LSP1基因rs3817198多态性位点基因型频率在乳腺癌和对照样本之间未存在显著差异(P=0.937、P=0.323)。Logistic回归分析结果显示,对于MAP3K1的rs889312位点,与AA携带者相比,AC携带者、CC携带者和AC+CC基因型携带者与乳腺癌的患病危险无关(OR=0.814,95%CI=0.537-1.236,P=0.335;OR=0.999,95%CI=0.627-1.594,P=0.998;OR=0.876,95%CI=0.591-1.298,P=0.509);对于LSP1的rs3817198位点,与TT携带者相比,CT携带者、CC携带者和CT+CC基因型携带者与乳腺癌的患病危险无关(OR=0.832,95%CI=0.565-1.223,P=0.349;OR=0.651,95%CI=0.108-3.936,P=0.640;OR=0.839,95%CI=0.573-1.229,P=0.369)。结论:上述两个基因MAP3K1和LSP1位点多态性与中国北方汉族绝经前妇女乳腺癌易感性之间无明显相关性。     

甘肃汉族女性XPF基因多态性与散发乳腺癌易感性的相关性分析

[目的]探讨着色性干皮病基因组F(XPF)rs3136189及rs1800067单核苷酸多态性(SNPs)与甘肃汉族妇女散发乳腺癌的关系。[方法 ]采用以自然人群为基础的病例对照设计,对101例乳腺癌和1∶1成组频数匹配原则获得的101例对照进行研究。基因分型采用聚合酶链反应-限制性内切酶片段长度多态性(PCR-RFLP)分析方法,采用非条件Logistic回归模型评估各SNP基因型与乳腺癌发病风险的关联。[结果]甘肃汉族妇女人群正常对照组XPF基因SNP位点rs3136189的TT、CT和CC基因频率分别为59.41%、39.60%和0.99%,而乳腺癌组分布频率分别为53.47%、40.59%和5.94%。rs1800067正常对照组的GG、AG和AA基因频率分别为98.02%、1.98%和0,乳腺癌组分别为99.01%、0.99%、0。2个SNPs位点基因型和等位基因在两组间分布差异均无统计学意义(P>0.05)。乳腺癌患者肿瘤大小、有无淋巴结转移及ER、PR、C-erb B-2、p53和Ki67蛋白表达与rs3136189位点基因型频率分布均无相关性(P>0.05)。[结论 ]甘肃汉族妇女人群XPF基因rs3136189及rs1800067多态性位点与乳腺癌的发病风险间未发现显著性关联。     

CYP1B1 variants are associated with prostate cancer in non-Hispanic and Hispanic Caucasians

Cytochrome P450 1B1 (CYP1B1) is involved in the activation of many carcinogens and in the metabolism of steroid hormones. We compared allele, genotype and haplotype frequencies of six single-nucleotide polymorphisms (SNPs) within CYP1B1 among non-Hispanic Caucasians (496 cases and 498 controls) and Hispanic Caucasians (153 cases and 240 controls). In the Hispanic Caucasians, the GG genotype for rs1056836 decreased the risk for prostate cancer (PCa) when compared with the CC genotype [odds ratio (OR) = 0.31, P = 0.04, 95% confidence interval (CI) = 0.10-0.96]. Among non-Hispanic Caucasian men with more aggressive PCa, the prevalence of several SNPs (rs2567206, rs2551188, rs2617266, rs10012 and rs1056836) was significantly associated with the disease status. A common C-G-C-C-G-A haplotype for rs2567206-rs2551188-rs2617266-rs10012-rs1056836-rs1800440 showed an inverse association with PCa risk in Hispanic Caucasians (OR = 0.19, P = 0.04, 95% CI = 0.04-0.95) and with aggressive disease status (i.e. Gleason score >or=7) in non-Hispanic Caucasian cases (OR = 0.64, P = 0.008, 95% CI = 0.47-0.89). In the non-Hispanic Caucasian cases, a second major haplotype T-A-T-G-C-A was positively associated with the high-grade disease status (OR = 1.77, P = 0.002, 95% CI = 1.24-2.53). Our findings suggest that genetic polymorphisms in CYP1B1 may modify the risk for PCa and support the role of CYP1B1 as a candidate gene for PCa.     

Interleukin-1 receptor antagonist haplotype associated with prostate cancer risk

IL1-RN is an important anti-inflammatory cytokine that modulate the inflammation response by binding to IL1 receptors, and as a consequence inhibits the action of proinflammatory cytokines IL1alpha and IL1beta. In this study, we hypothesise that sequence variants in the IL1-RN gene are associated with prostate cancer risk. The study population, a population-based case-control study in Sweden, consisted of 1383 prostate cancer case patients and 779 control subjects. We first selected 18 sequence variants covering the IL1-RN gene and genotyped these single-nucleotide polymorphisms (SNPs) in 96 control subjects. Gene-specific haplotypes of IL1-RN were constructed and four haplotype-tagging single-nucleotide polymorphisms (htSNPs) were identified (rs878972, rs315934, rs3087263 and rs315951) that could uniquely describe >95% of the haplotypes. All study subjects were genotyped for the four htSNPs. No significant difference in genotype frequencies between cases and controls were observed for any of the four SNPs based on a multiplicative genetic model. Overall there was no significant difference in haplotype frequencies between cases and controls; however, the prevalence of the most common haplotype (ATGC) was significantly higher among cases (38.7%) compared to controls (33.5%) (haplotype-specific P = 0.009). Evaluation of the prostate cancer risk associated with carrying the 'ATGC' haplotype revealed that homozygous carriers were at significantly increased risk (odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.2-2.2), compared to noncarriers, while no significant association was found among subjects heterozygous for the haplotype (OR = 1.0, 95% CI = 0.8-1.2). Restricting analyses to advanced prostate cancer strengthened the association between the 'ATGC' haplotype and disease risk (OR for homozygous carriers vs noncarriers 1.8, 95% CI = 1.3-2.5). In conclusion, the results from this study support the hypothesis that inflammation has a role of in the development of prostate cancer, but further studies are needed to identify the causal variants in this region and to elucidate the biological mechanism for this association.     

Association of CD27 and CD70 gene polymorphisms with risk of sporadic breast cancer in Chinese women in Heilongjiang Province

CD27 and its ligand, CD70, are major costimulatory molecules whose interaction can regulate the expansion and differentiation of effector and memory T-cell populations. Their abnormal expression can disturb the immune response and lead to an increased risk of cancer. This study aims to evaluate the associations between single nucleotide polymorphisms (SNPs) in CD27/CD70 gene and breast cancer susceptibility. Five tagSNPs and one coding polymorphism in CD27, as well as three tagSNPs in CD70, were genotyped in a case-control study of 610 breast cancer patients and 617 healthy controls. In CD27, rs3136550 CT and rs2267966 AT genotypes were associated with a decreased risk of breast cancer (P = 0.03, OR = 0.76; P = 0.02, OR = 0.75, respectively). In CD70, AG and GG genotypes in rs1862511 and CC genotype in rs2059154 also showed significant associations with a decreased risk of breast cancer (P = 2.00 × 10(-3), OR = 0.69; P = 0.03, OR = 0.62; P = 2.00 × 10(-3), OR = 0.53; respectively). Significant associations were also found in the dominant and recessive models for rs2059154 and dominant model for rs1862511. In haplotype analysis, CCGAG haplotype in CD27 and TAA haplotype in CD70 conferred an increased risk of breast cancer (P = 5.60 × 10(-3); P = 7.75 × 10(-5), respectively), but TGC, TAC and TGA haplotypes in CD70 were associated with a decreased risk of breast cancer (P = 0.01; P = 5.2 × 10(-3); P = 2.00 × 10(-3), respectively). The associations of CCGAG, TAA, TAC and TGA haplotypes remained significant after correcting P value for multiple testing. Significant associations were shown between the SNPs of CD27 and lymph node metastasis, and ER and PR statuses. These results indicate that CD27 and CD70 gene polymorphisms may affect the risk of breast cancer and show that some SNPs are associated with breast cancer characteristics in a northern Chinese population.     

The DNA repair gene XRCC1 and genetic susceptibility of lung cancer in a northeastern Chinese population

To evaluate the effect of DNA repair gene XRCC1 polymorphisms on the risk of lung cancer in a northeastern Chinese population, we studied five cSNPs in the XRCC1 gene, three that lead to non-synonymous changes: Arg194Trp, Arg280 His and Arg399Gln and two that lead to synonymous changes: Pro206Pro and Gln632Gln. A hospital-based case-control study consisted of 247 lung cancer cases and 253 cancer-free controls matched on age, gender and ethnicity. PCR-RFLP was used for genotyping. Carriers of the minor G-allele of Pro206Pro were at significantly increased risk of lung cancer (adjusted OR=1.96, 95% CI=1.26-3.06, P=0.003). Stratified analyses revealed a significantly decreased risk of lung cancer associated with the AG/AA genotype of Arg280His (AG+AA versus GG, OR=0.38, 95% CI=0.19-0.75, P=0.005) among never smokers, although there was no interaction between Arg280His and smoking. In a haplotype analysis, a haplotype defined by Arg194Trp(C)-Pro206Pro(G)-Arg280His(G)-Arg399Gln(G)-Gln632Gln(G) was associated with increased risk of lung cancer (OR=28.60, 95% CI=2.49-331.31, P=4.45x10(-5)). No associations were observed for the other polymorphisms or haplotypes. Our results suggest that the XRCC1 Pro206Pro polymorphism or the haplotype encompassing the minor allele may contribute to genetic susceptibility for lung cancer in this northeastern Chinese population. To our knowledge, this is first report that XRCC1 Pro206Pro influences cancer risk.     

Association of polymorphisms in base excision repair genes with the risk of breast cancer: a case-control study in North Indian women

Inheritance of common genetic variants at one or more base excision repair (BER) genes may result in a reduced DNA repair capacity and in an increased risk of cancers like breast cancer. The present case-control study with 390 north Indian women (155 breast cancer cases and 235 controls) was aimed to investigate the association of seven nonsynonymous BER gene polymorphisms viz. rs1130409/T1865G (APEX1), rs1799782/T22142C (XRCC1), rs25487/G23990A (XRCC1), rs4989588/T3337A (FEN1), rs4989586/ G3259A (FEN1), rs4989587/C3315T (FEN1), and rs1050525/G6941T (PCNA) with breast cancer susceptibility. Statistically significant association with breast cancer risk was observed for rs1130409 homozygous mutant GG [odds ratio (OR) 3.35, 95% confidence interval (CI) 1.36-8.26), heterozygous GT (OR 2.42, 95% CI 1.56-3.76), and combined mutant (GT + GG) (OR 2.52, 95% CI 1.65-3.86] genotypes and rs25487 homozygous mutant AA (OR 2.91, 95% CI 1.66-5.10) and combined mutant (AA + AG) (OR 1.41, 95% CI 0.903-2.19) genotypes, whereas protective association was exhibited by rs1799782 homozygous mutant CC (OR 0.413, 95% CI 0.082-2.08), heterozygous TC (OR 0.351, 95% CI 0.189-0.650), and combined mutant (TC + CC) (OR 0.357, 95% CI 0.199-0.641) genotypes. Association study using reconstructed haplotypes of XRCC1 gene showed positive association for the TA haplotype (OR 2.014, 95% CI 1.462-2.775) and a protective association for the CG haplotype (OR 0.173, 95% CI 0.052-0.576) pertaining to breast cancer risk. The results indicate that the polymorphisms rs1130409 (APEX1) and rs25487 (XRCC1) might be involved in contributing towards breast cancer susceptibility, while rs1799782 (XRCC1) might have protective influence.