Abstract: Objective The aim of the present study was to explore whether genetic polymorphisms oflymphotoxin-alpha (LTA) gene are risk factors for noncardiogenic ischemic stroke in HanChinese population.Methods Three common variants of LTA, rs1800683, rs909253 and rs1041981, were genotypedin a sample including 558 noncardiogenic ischemic stroke cases and 557 normal controls usingTaqman-MGB assay in a case-control study. The association analyses were performed at bothsingle nucleotide polymorphism and haplotype levels. Bonferroni correction was applied formultiple corrections.Results No significant association were found between any of these LTA alleles or genotypeswith risk of noncardiogenic ischemic stroke. When AGA haplotype was chosen as the baseline foradjusting conventional risk factors, the protective effect for haplotype GGC remained significant(AGA versus GGC; OR , 0.381; 95%CI , 0.198 to 0.733; P =0.003).Conclusion The GGC haplotype of LTA maybe a protective factor in pathogenesis ofnoncardiogenic ischemic stroke warrants further confirm in a prospective study.

Key words: Brain infarction; lymphotoxin-alpha; Polymorphism; single nucleotide

摘要： 目的 在中国汉族人群中研究淋巴毒素α（lymphotoxinα，LTA）基因多态性位点是否为非心源性缺血性卒中的危险因素。方法 采用Taqman-MGB探针法在558名非心源性缺血性卒中患者和557名健康成人中对LTA的rs1800683、rs909253、rs1041981三个多态性位点进行基因分型。在单核苷酸多态性水平和单体型水平进行关联分析，并使用Bonferroni法进行多重检验校正。结果 LTA的三个单核甘酸多态性的不同等位基因和基因型在非心源性缺血性卒中组和对照组分布未见统计学差异。以最常见的单体型AGA作为参照，在校正传统危险因素后，GGC携带者有0.381倍卒中发病风险（95%CI：0.198～0.733，P =0.003）。结论 GGC单体型可能是非心源性缺血性卒中发病的保护性因素，有待于在前瞻性研究中进一步证实。

关键词: 脑梗死; 淋巴毒素α; 多态性; 单核甘酸