摘要目的研究中国人FVLeiden基因突变引起的抗活化蛋白C现象(APCR)。方法采用APTT±APC方法、多聚酶链反应(PCR)、MnLI限制性内切酶分析，序列特异性引物(PCR-SSP) 和DNA测序方法，对中国汉族30例“正常”无关个体和20例血栓性疾病患者进行APCR测定和FVLeiden 基因突变分析。 结果发现一例正常人抗APC敏感值比值(APC-SR)明显减低(0.8)，并确诊为FVLeiden基因(Arg506- Gln)突变杂合子，其叔祖父、父亲、弟弟和儿子同样确定为FVLeiden基因杂合子；有3例血栓性疾病患者 APC-SR低于正常，但均无FVLeiden基因突变。 结论这是在国内发现的首例四代FVLeiden突变所致的APCR现象的家系。中国人血栓症中APCR的产 生是否导致其它未知的基因缺陷，尚待进一步研究。

abstractsObjective To investigate the factor V Leiden mutation associatedwith activated protein C resistance (APCR) in Chinese. Methods Thirty “normal" individuals and twenty patients with thrombotic disease from Chinese Han Nationality were studied with APTT±APC, PCR followed by MnLI restriction enzyme analysis,PCR based direct sequence-specific primers (PCR-SSP) and DNA sequence analysis. Results In one healthy control, the activated protein C (APC) sensitivity ratio (SR) was found to be significantly lower (0.8) than that in other normal control (>2.0). This individual was identified to be heterozygous for FV Leiden mutaiton (Arg506-Gln). His grand-uncle, father, brother and son were also identified to be heterozygous for FV Leiden. The APC resistance was found in 3 other cases of thrombotice diseases, but with no FV Leiden mutation. Conclusion This is the first four generations family case of FV Leiden mutation associated with APCR reported within Chinese ethnic population. It is note-worthy that more FV Leiden or whether other gene defects may be associated with APC resistance and acquired APCR causing thrombosis in Chinese population.