糖尿病孕妇胎盘胰岛素生长因子2和其交互印迹基因H19表达及印迹状态变化

Alterations of expression and imprinting status of Insulin-like Growth Factor 2 and H19 in diabetes mellitus patients＇ placenta

目的了解胰岛素生长因子2（1GF2）和H19基因在糖尿病与非糖尿病孕妇胎盘中表达水平以及印迹状态的变化。方法选取2009年2月至9月在北京大学第一医院分娩的糖尿病孕妇33例为病例组，其中妊娠期糖尿病（GDM）患者23例，糖尿病合并妊娠患者10例，同期分娩的无妊娠合并症的非糖尿病孕妇31名为对照组。提取胎盘组织中的RNA和DNA，采用实时定量聚合酶链反应（real—timePCR）方法比较病例组和对照组中IGF2和H19基因表达量的变化，采用限制性片段长度多态性（RELP）方法比较2者印迹状态的变化。统计学方法采用非配对样本t检验。结果（1），G砣基因在病例组胎盘中表达量高于对照组，差异具有统计学意义（分别为2．4±1．2、1．94-0．8，t：-2．2，P〈0．05）；H19基因在病例组胎盘中表达量高于对照组，但差异无统计学意义（分别为7．2±3．6、6．14-2．7，t=-1．5，P〉0．05）；（2）IGF2基因Apal位点的杂合率为60．9％（39／64），H19基因Rsal位点的杂合率为34．4％（22／64）；（3），GF2基因Apal位点和H19基因Rsal位点在病例组和对照组杂合子胎盘中均无印迹丢失。结论（1）IGF2基因在糖尿病孕妇胎盘中表达量增加；（2）IGF2基因和H19基因在糖尿病孕妇胎盘中无印迹丢失发生，是否发生其他位点或DMR区的甲基化变化仍有待于进一步研究。

Objective To investigate the alterations of expression and imprinting status of insulin growth factor 2 （IGF2） and H19 gene in diabetes mellitus patients＇ placenta. Methods 66 pregnant women delivered between February to September 2009 were inrolled, 33 cases with diabetes mellitus （Patient group, GDM 23 cases （NDDG （National Diabetes Data Group） criteria） , DM 10 cases） and 31 cases with normal glucose tolerance（ Control group）. RNA and DNA were extracted from the placenta of all objects. Real-Time PCR was performed to compare the expression of IGF2 and H19 gene in different groups, and RELP was used to identify the alternations of imprinting status . Statistical analyses were done by SPSS software （V10.0, SPSS Inc, USA）. P values 〈 0.05 were considered statistically significant. Results （ 1 ） Compared with the control group, the expression of IGF2 gene was significantly higher （ 2.4 ± 1.2 vs 1.9 ± 0.8, t = - 2.2, P 〈 0.05 ） in the patients groups. The expression of H19 gene was higher （7.2 ± 3.6 vs 6.1 ± 2.7,t = - 1.5, P 〉 0. 05 ） in the patient group compared with that of control group, whereas there were no significant difference between them. （2） The genetic heterogeneity of 1GF2 gene Apal locus was 60.9% （39/64） , and the geneticheterogeneity of II19 gene Rsal locus was 34.4% （22/64）. （3） The expression of IGF2 gene Apal locus and H19 gene Rsal locus was no loss of imprinting in the patient group and the control group. Conclusion （ 1 ） The expression of IGF2 gene is increased in the placenta of diabetes mellitus patients. （2） The expression of IGF2 and H19 gene in the placenta of gestational hyperglycemia patients has no loss of imprinting.