Lin28/let-7调控区SNP对妊娠期糖尿病易感性的影响与机制研究

Effect and mechanism of Lin28/let-7 on the susceptibility of gestational diabetes mellitus in SNP control area

目的探究Lin28/let-7调控区SNP对妊娠期糖尿病(GDM)易感性的影响,从基因角度为妊娠期糖尿病的检测提供依据。方法选取2013年1月至2015年12月收治的212例患有妊娠期糖尿病的孕妇为观察组,同期入院进行检的262例正常孕妇为对照组,收集所有孕妇外周血样本。比较两组患妊娠期糖尿病指标,采用Real-time PCR对两组患者let-7的表达水平进行检测,采用生物信息学方法对两组患者let-7上3个前提启动子调控区域标签进行检测和筛选。使用聚合酶链式反应-限制性片段长度多态性法对所有患者前期检测筛选出的3个SNP进行基因分型。采用RT-qPCR、Western blotting和免疫组织化学方法对胎盘组织中的Lin28B基因以及Lin28基因表达生成的蛋白进行检测,并比较基因和蛋白差异及细胞定位。结果 Real-time PCR监测结果发现,观察组多数患者let-7基因表达水平较对照组低,差异具有统计学意义(P<0.05);rs3811463、rs3811464以及rs11247955三个结合位点的预测杂合度最高。结论 Lin28/let-7的基因多态性与GDM的易感性相关,其机制可能为Lin28基因的非同义突变改变了Lin28或let-7的表达水平,Lin28与let-7进一步平衡放大,进而影响细胞的糖代谢和胰岛素敏感性,从而造成个体对GDM遗传易感性的变化。

Objective To explore the effect of Lin28/let-7 regulation area SNP on the susceptibility of gestational diabetes mellitus,and to provide evidence for the detection of gestational diabetes mellitus. Methods 212 cases of pregnant women with gestational diabetes were selected as the observation group,262 cases of normal pregnant women admitted to hospital during the same period were collected as control group. Peripheral blood samples from all pregnant women were collected. Two groups of patients with gestational diabetes indicators were compared,the expression level of Real- time PCR in two groups of patients with let-7 were detected by the method of bioinformatics,two groups of patients with let-7 on the 3 premise of promoter tag were detected and screened. polymerase chain reaction restriction fragment length polymorphism method was used to detect the 3 SNP genes in all patients. Western,blotting RT- qPCR and immunohistochemistry methods were used to detect the expression of Lin28 B gene and Lin28 gene in placenta tissue,and to compare the difference of gene and protein and cell location. Results PCR Real- time monitoring results found that the expression level of the two groups of patients with let- 7 was statistically significant（P〈0.05）.Rs3811463 loci in the GDM medium frequency of two groups of patients with statistically significant difference. Conclusion The susceptibility gene of GDM was correlated with polymorphism of Lin28/let-7. The possible mechanism for non synonymous mutations may be that the Lin28 gene changed the expression level of Lin28 or let-7,Lin28 and let-7 further balanced and amplified,thereby affecting the cell glucose metabolism and insulin sensitivity,resulting in individual variation on genetic susceptibility of GDM.