ADTRP基因剪切位点变异c.154-18delT与静脉血栓形成的关联及其导致易栓状态的分子机制研究

Venous thrombosis is a complex multi-genetic disease. Its genetic background is largely unkown. Recenlty, two independent genome-wide association studies indicated that variations locating adjacent to the unknown genomic region of C6orf105 might be linked to thrombotic disease. Further functional study showed that the protein encoded by this locus was a positive regulator for tissue factor-pathway inhibitor and had potential anticoagulant properties. It was named as androgen-dependent TFPI regulating protein (ADTRP). Thus, ADTRP is a novel candidate gene for thrombosis. The investigation on the existence of genetic variation that could increase the risk for thrombosis is warranted. By using a deep resequencing strategy, we showed for the first time that an insertion-deletion polymorphism within the splicing boundary of ADTRP exon 2, c.154-18delT, could reduce the mRNA splice efficiency. By using a genotyping study, we found that the variant was present in approximately 22.4% of general population in homozygous state, which could have a 2-fold increased risk for thrombosis, indicating that the c.154-18delT is a common genetic risk factor for venous thrombosis. In this proposal, we intend to explore the association between the ADTRP polymorphisms and venous thrombosis, and the relative risk of the variant for thrombosis by using a case-control study involving a huge number of participants. In addition, we intend to investigate the molecular mechanisms by which the c.154-18delT could induce a thrombophilic state by using a “mini-gene” method, GST-pull down analysis and so on. Individuals at high-risk for thrombosis will benefit from thrombosis-risk prediction and the molecular basis of thrombosis caused by the ADTRP polymorphism will provide new methods for anti-thrombotic targeting therapy.

静脉血栓形成的遗传易感因素有很大探索空间。近年来2项全基因组关联研究提示在C6orf105区域可能存在与血栓性疾病相关的基因变异。随后研究发现该基因座的编码产物具有调节组织因子途径抑制物表达的抗凝血功能，命名为肾上腺素依赖的TFPI调节蛋白（ADTRP）。因此，ADTRP变异是否增加血栓风险值得探讨。通过重测序我们在ADTRP的2号外显子剪切区域发现了1种缺失型多态性c.154-18delT，能够减弱mRNA的剪切效率；初步基因分型研究表明，该变异在普通人群约占22.4%，血栓形成优势比约为2，提示该多态性是静脉血栓形成的常见危险因素。本项目拟通过大样本的病例-对照研究明确ADTRP多态性与静脉血栓形成的关联及其相对危险度；用“mini基因”、GST-pull down等方法研究c.154-18delT变异导致易栓状态的分子机制。研究有望服务于血栓风险筛查，为抗栓的靶向治疗提供新依据。

静脉血栓形成的遗传易感因素有很大探索空间。近年来2项全基因组关联研究提示在C6orf105区域可能存在与血栓性疾病相关的基因变异。随后研究发现该基因座的编码产物具有调节组织因子途径抑制物表达的抗凝血功能，命名为肾上腺素依赖的TFPI调节蛋白（ADTRP）。因此，ADTRP变异是否增加血栓风险值得探讨。本项目通过重测序我们在ADTRP的2号外显子剪切区域发现了1种缺失型多态性c.154-18delT，能够减弱mRNA的剪切效率；基因分型研究表明，该变异在普通人群约占22.4%。通过大样本的病例-对照研究明确了ADTRP多态性与静脉血栓形成的关联，ADTRP c.154-18delT是VTE的危险因素，在显性模型下c.154-18delT突变携带者患血栓性疾病的风险是非携带者的1.25（95% CI, 1.01-1.56, P=0.043）倍。该多态性可作为血栓性疾病的遗传学诊断指标，纳入血栓风险评估模型，在普通人群或者易栓症家族中推广筛查，使高危人群获益于早期诊断和预防。