先天性凝血因子Ⅴ缺乏症的一种新基因突变的鉴定

目的 探讨先天性凝血因子Ⅴ（FⅤ）缺乏症的分子发病机制。方法 利用发色底物法检测血浆FⅤ凝血活性，采用PCR产物直接测序或T－A克隆后测序，限制性酶切分析先证FⅤ基因，并进行家系和FⅤ基因多态性频率研究。结果 先证18号外显子存在G5729T（M16967）的纯合子突变，相应的氨基酸变异为Gly1880Val,FⅤ分子结构分析表明，突变后FⅤ的重链和轻链结合松弛。结论 FⅤ基因G5729T突变与先天性FⅤ缺乏症的发病有关。

Identification of a novel mutation of human blood coagulation FV gene associated with congenital FV deficiency]

OBJECTIVE: To explore the molecular mechanisms involved in the patient with congenital FV deficiency. METHODS: Activity of FV was determined by biochemical method. The PCR products of FV gene was analysed by directly sequencing or sequencing after cloned into T-vector. The mutative FV gene was analysed by restriction enzyme analysis in the proband and her family members. RESULTS: A homozygous missense mutation G5729T resulting in Gly1880Val was revealed in the proband and confirmed in the family screening. Structure-function studies of the factor V mutants (Gly1880Val) demonstrated the importance of Gly1880 for structural stability of the Factor V. CONCLUSION: G5729T mutation of FV gene is related to the pathogenesis of congenital FV deficiency.