孕妇血中胎儿细胞在产前诊断中的初步应用──胎儿SRY基因的鉴定  

DETECTION OF FETAL CHROMOSOME-SPECIFIC SRY GENE IN MATERNAL PERIPHERAL BLOOD

作　　者：马旭[1] 张思仲[1] 罗安雪 李莉莎 赵丽[1] 

机构地区：[1]华西医科大学医学遗传室,国家计划生育委员会科研所遗传室,成都市妇产医院遗传室,成都市第一人民医院妇产科

出　　处：《中华医学遗传学杂志》1995年第5期265-268,T018,共4页Chinese Journal of Medical Genetics

基　　金：国家自然科学基金;美国纽约医学基金

摘　　要：以Ｎｙｃｏｄｅｎｚ和Ｐｒｅｃｏｌｌ作为分离介质，对２３名孕龄为６～４１周，年龄为２１～２８岁的孕妇外周血中胎儿细胞进行了密度梯度离心富集。其中１５名怀男胎孕妇外周血富集前后各类细胞ＳＲＹ基因的ＰＣＲ扩增检查表明，大部分孕妇外周血多核细胞及低密度单个核细胞扩增结果为阳性，与胎儿实际性别符合率分别为８０．０％和９３．３％．这一结果提示：（１）ＰＣＲ分析母血中胎儿细胞单拷贝基因应采用低密度细胞多核细胞，且以前者为优；（２）密度梯度离心法已在一定程度上从母血中富集胎儿细胞，且所获得的细胞已基本上满足了ＰＣＲ扩增单拷贝基因所需的模板量；（３）富集实验证实母血中胎儿细胞大致由多核细胞及低密度单个核细胞两部分组成，而未经富集的孕妇血单个核细胞及高密度细胞中仅有少数几例呈ＳＲＹ阳性，符合率分别为１３．３％和６．７％；提示从未富集的孕妇外周血中按常规方法难以扩增出含量极微的胎儿单拷贝基因。在对３名怀女胎的孕妇外周血富集前后各类细胞共３２份标本进行ＳＲＹ基因的检测时，出现３例假阳性结果，其原因不明，不能排除外源男性ＤＮＡ的污染或前次妊娠的残留胎儿细胞的干扰所致。The development of the polymerase chain reaction opens up new possibilities for fetal diagnosis from maternal peripheral blood.In this study,SRY gene of fetal cells from 15 peripheral blood samples of pregnancy with male was detected both before and after enrichment which is a one-step procedure designed to enrich the fetal cells from maternal blood,using discontinuous density gradient centrifugation ,by confirmation with PCR technique.It was found that SRY gene was amplified mainly from polykaryocytes and low-density mononuclear cells,and the concordance rate with real fetal sex was 80.8% and 93.3% respectively; meanwhile the SRY gene detection of unenriched and high-density mononuclear cell was only 13.3% and 6.7%. The results indicate that polykaryocytes and low-density mononuclear cells are the most favourable cell fractions for fetal SRY gene detection and they also are the fetal cells in maternal blood. With properly designed amplification protocal,the results may be an alternative of determining the fetal sex for those pregnancies at the risk of X-linked genetic disease and other gene disorders.

关 键 词：孕妇 胎儿细胞 胎前诊断 SRY基因 性别鉴定 

分 类 号：R714.55[医药卫生—妇产科学]