摘要
孕妇血浆中胎儿游离DNA,源于胎儿细胞和/或胎盘的凋亡,经核酸内切酶选择性地剪切为313 bp以下的短片段分子,因相对含量丰富,成为了当前无创伤性产前分子遗传诊断中胎儿DNA的重要来源,业已开展了胎儿性别鉴定、RhD阴性孕妇的Rh(D)基因检测、胎儿非整倍体病的诊断、STR遗传标记检测等应用研究。根据胎儿游离DNA的浓度、纯度、分子片段大小分布的特征和检测的靶基因,采用相应的分子基因诊断策略和实验设计,限制扩增产物的片段长度,有助于提高无创伤性产前胎儿分子遗传诊断的成功率。当前,大规模并行基因组测序技术为直接利用胎儿游离DNA进行无创伤性产前基因诊断开辟了新途径。
Cell-free fetal DNA in maternal plasma of pregnant woman,originating from fetal and/or placental cells undergoing apoptosis,is mainly the short-sized DNA fragments of less than 313 base pairs in length because fetal DNA is cleaved selectively by nuclear endonuclease during the apoptosis process.With relatively high abundance in maternal plasma,circulating fetal DNA has now become an important source for non-invasive prenatal molecular genetic diagnosis and is widely used in fetal sex-determination,gene testing of fetal Rh（D） in the plasma of the rhesus-negative pregnant woman,fetal aneuploidy detection,fetal STR genotyping and other clinical applications.Based on the characteristics of cell-free fetal DNA concentration,purity,size distributions and the target gene,the appropriate molecular diagnosis strategy and experimental design as well as restricting the length of PCR product will help improve the accuracy of non-invasive prenatal diagnosis.The massively parallel genomic sequencing provides a new approach for non-invasive prenatal diagnosis using the cell-free fetal DNA from maternal plasma.
出处
《实验与检验医学》
CAS
2012年第1期1-3,32,共4页
Experimental and Laboratory Medicine
基金
广东省科技计划资助项目(2008B030301277)
