目的　从分子遗传学水平进行基因多态性研究 ,探讨血浆纤溶酶原激活物抑制剂 1(plasminogenactivatorinhib itor 1,PAI 1)基因启动子区单核苷酸缺失 插入 (4G 5G)多态性与周围动脉闭塞性疾病之间的关系 ,以期阐明遗传易感因素在该疾病中的作用。方法　将研究对象分为 3组 :正常对照组 (Ⅰ组 )、原发性高血压病组 (Ⅱ组 )以及原发性高血压合并周围动脉闭塞性疾病组 (Ⅲ组 ) ,每组均选取 10 0例 ,应用等位基因特异性聚合酶链反应分别对其进行PAI 1基因启动子 4G 5G多态性分析。结果　第Ⅲ组PAI 1基因启动子 4G 4G基因型频率 (0 .4 6 )及 4G等位基因频率 (0 .6 5 )与第Ⅰ组 (0 .2 7和 0 .5 3)及第Ⅱ组 (0 .2 9和 0 .5 5 )相比较 ,差异有显著性意义 ,而第Ⅰ组与第Ⅱ组间差异则无显著性意义 ;第Ⅲ组的总胆固醇、低密度脂蛋白胆固醇水平均明显高于第Ⅰ组及第Ⅱ组 ,差异有显著性意义。结论　PAI 1基因启动子区 4G 5G的多态性可能与周围动脉闭塞性疾病有关 ,其 4G 4G基因型可能是该病的一个危险因素 Objective To investigate the gene polymorphism at the level of molecular genetics and to explore the relationship between the single nucleotide missense insertion (4G 5G) polymorphism in the plasminogen activator inhibitor 1 (PAI 1) Peripheral arterial occlusive disease in order to clarify the role of genetic predisposition in the disease. Methods The subjects were divided into three groups: normal control group (group Ⅰ), essential hypertension group (group Ⅱ) and essential hypertension combined with peripheral arterial occlusive disease group (group Ⅲ) One hundred and ten cases were analyzed by allele-specific polymerase chain reaction (PCR) for the 4G 5G polymorphism of PAI 1 gene promoter. Results The frequency of 4G 4G genotype of PAI 1 gene promoter in group Ⅲ (0.46) and the frequency of 4G allele (0.56) were significantly different from those in group Ⅰ (0.27 and 0.53) and Ⅱ Group (0 .29 and 0 .5 5) compared to the difference was significant, while the first group and the second group was no significant difference between the difference; the third group of total cholesterol, low density lipoprotein cholesterol levels Were significantly higher than the first group and the second group, the difference was significant. Conclusion The polymorphism of 4G 5G in PAI 1 gene promoter region may be related to peripheral arterial occlusive disease. The 4G 4G genotype may be a risk factor for the disease