一个遗传性凝血因子Ⅴ缺陷症家系的基因分析

Gene analysis on a pedigree with coagulation factor V deficiency

目的:探讨无出血症状凝血因子Ⅴ(FⅤ)缺陷症的分子病理机制。方法:检测先证者及其家系成员的活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)、凝血酶时间(TT)等;采用一期法测定血浆凝血因子活性,PCR法扩增FⅤ25个外显子及其侧翼序列,纯化测序后与Genbank里的标准序列(AY364535)比对,以发现基因变异。结果:先证者APTT、PT显著延长,分别为104.1s和31.5s,凝血因子Ⅴ活性(FⅤ:C)4%;先证者及家系成员基因分析发现13、15和16号外显子存在12个单核苷酸多态性(SNP)位点,基因型为纯合型和复合杂合型,尚未发现新的基因突变位点。结论:凝血因子Ⅴ缺陷症无出血症状与B结构域的SNP位点有关。

Objective：To explore the molecular and pathologic mechanism of hereditary deficiency of coagulation factorⅤ（FⅤ） in patients without haemorrhage symptom.Method：The activated partial thromboplastin time（APTT） ,prothrombin time（PT） ,thrombin time（TT） of the proband and family members were detected.The level of FⅤin plasma was determined by a one-stage cloting assay.All the exons and exon-intron boundaries of the F5 gene were amplified from the proband＇s genomic DNA by polymerase chain reaction（PCR） .PCR products were directly sequenced and compared with GenBank AY364535sequence to discover the gene mutation.Result：The proband showed significantly prolonged APTT and PT values,which were 104.1 sand 31.5s,and FⅤ：C was 4%;12 single nucleotide polymorphism（SNP） sites were found at exon 13,exon 15 and exon 16by blast. The genotype of the proband and family members were homozygote or compound heterozygote.No new gene mutation was found by gene analysis.Conclusion：Non-haemorrhage symptom in hereditary deficiency of coagulation factorⅤwas related to the SNP sites of FⅤ＇s B domain.