唐氏综合征产前诊断研究进展

中国每年约有3万唐氏综合征患儿出生,在各种出生缺陷中排第三位,是最常见的染色体异常.为了减少唐氏综合征患儿的出生,近年绒毛、羊水、脐血介入性产前诊断已广泛开展,使部分唐氏综合征得到产前诊断,并行治疗性引产,降低了唐氏综合征患儿的出生率,但侵入性手术操作的风险和诊断结果的漫长等待亦给孕妇造成了巨大的心理压力.因此,植入前产前诊断、分离孕妇外周血中胎儿有核红细胞、分离孕妇血浆中胎儿游离DNA、宫颈管内滋养细胞等新技术正在展开研究,已经成功地无创性获取胎儿细胞或DNA样本.荧光定量PCR、荧光原位杂交技术（FISH）、引物原位标记技术（PRINS）、微阵列-比较基因组杂交等分子生物学技术等为快速、准确诊断唐氏综合征开辟了新前景.现就唐氏综合征产前诊断基础性研究及临床应用的进展情况作一综述.

A review on prenatal diagnosis of down syndrome

Every year, there are about 30 thousand babies born with Down syndrome（DS） in China, which ranks the third among all kinds of birth defects. In order to reduce the birth of babies with DS, the iuterventional prenatal diagnoses, such as chorionic villus sampling, amniocentesis and cordoeentesis, have been widely carried out in recent years, which has reduced the birth of babies with DS. However, the risk of invasive operation and the long pe- riod of waiting will cause the heavy mental pressure of pregnant women. Therefore, the study on a series of new tech- niques has been developed, including preimplantation genetic diagnosis, isolation of fetal nucleated red blood cells from maternal peripheral blood, isolation of cell-free fetal DNA in maternal plasma, endocervlcal fetal trophoblast. The fetal cells or DNA samples have been successfully obtained with those non-invasive methods. Moreover, the tech- piques of molecular biology have brought new prospects to the rapid and accurate diagnosis of DS, including fluores- cence quantitative polymerase chain reaction （PCR）, fluorescence in situ hybridization （FISH）, primed in situ labe- llng （PRINS） and array comparative genomic hybridization （Array-CGH）. In this paper, we aim to make a summary on the progress of the basic research and clinical application of prenatal diagnosis for DS.