Cdc27基因变异在先天性心脏病家系中的机制研究

Congenital heart disease is mainly caused by the role of genetic and environmental factors, of which genetic factors have a greater impact, but the specific genetic basis and pathogenesis is not completely clear. Studies have shown that cdc20, cdc42 gene mutation which are the members of cell division cycle genes leading to congenital heart disease, and may through down-regulation of the wnt/β-catenin/cyllin signaling pathway. Our previous research team found an atrial septal defect pedigrees that the cdc27 gene SNP sites rs78493795, rs112848754 were nonsynonymous and frameshift deletion. At present, cdc27 gene is not involved in the development of heart, but it leading to rare tumors through wnt / β-catenin signaling pathway. Whether these mutations are involved in the pathogenesis of congenital heart disease is still unknown. In this proposal, Based on the previous study, further measures of cell biology, verification in populations and other premature congenital heart disease pedigrees, cellular and animal models using different intervention should be used to reveal the mechanism of the new variation of cdc27 gene in the development of congenital heart disease，to identify susceptible populations，and to provide a theoretical basis for the individual intervention.

先心病的发生主要是由遗传及环境因素作用所致，其中遗传因素影响更大，但具体遗传基础及发病机制尚不明确。有研究显示细胞周期分裂因子cdc20，cdc42基因变异影响基因功能而导致先心病，并可能通过下游信号通路wnt/β-catenin/cylin的下调导致发育缺陷。我们前期通过对1个完整的房间隔缺损家系血样研究，发现在cdc27基因SNP位点rs78493795、rs112848754处分别发生了错义突变和移码缺失。cdc27基因目前未有其参与心脏发育的相关报道，但可通过wnt/β-catenin导致少见肿瘤。该位点是否参与先心病的发生及发病机制尚不明确。基于此，本项目拟通过家系和人群的验证，细胞水平功能研究以及cdc27基因敲除小鼠模型等方法进行整体功能研究，以期能揭示cdc27基因变异在先心病发生中的作用及其机制，为早期识别易感人群，实现早期个体化干预奠定理论基础。

先天性心脏病是由遗传和环境因素共同导致。前期的对1个完整的房间隔缺损的家系行全基因组测序发现cdc27基因SNP位点rs78493795、rs112848754处分别发生了错义突变和移码缺失。为进一步验证该位点是否参与先天性心脏病的发生，本研究通过收集先天性心脏病人群，利用全基因组测序技术对相关基因进行全基因组测序，结果发现：（1）在汉族人群中，cdc27基因rs221603、rs1713494位点与先天性心脏病的发生相关；cdc42基因rs17837951位点与先天性心脏病发生相关。维吾尔族人群中rs67861319、rs858678位点与先天性心脏病的发生相关；cdc42基因rs74941957位点与先天性心脏病发生相关。（2）单倍型研究发现，汉族人群中cdc27-1 TTGCG单倍型与CHD的发生相关；维吾尔族人群中cdc27-1 TCG、cdc42 TGCCA单倍型与CHD的发生相关。此外，收集10w新鲜人胚流产组织，根据术前超声分为有胎心组和无胎心组。进行单细胞RNA测序。测序结果显示：有胎心搏动心脏单细胞RNA测序有cdc20、cdc27、cdc42基因的表达，无胎心搏动胚芽组织单细胞RNA测序未发现cdc20、cdc27、cdc42基因的表达。本研究揭示cdc20、cdc27、cdc42基因变异在先天性心脏病发生中的作用。为早期识别易感人群，实现早期个体化干预奠定。