Bryndorf T, Christensen B, Philip J, Hansen W, Yokobata K, Bui N, Gaiser C
Department of Obstetrics and Gynaecology, University Hospital/Rigshospitalet, Copenhagen, Denmark.
BMJ. 1992 Jun 13;304(6841):1536-9. doi: 10.1136/bmj.304.6841.1536.
To devise and evaluate a rapid screening method for detecting trisomy 21 (Down's syndrome) in samples of uncultured amniotic fluid cells.
Non-radioactive in situ hybridisation with HY128, a 500,000 base pair yeast artificial chromosome probe specific for chromosome 21. Blinded study of 12 karyotypically normal amniotic fluid samples and eight samples trisomic for chromosome 21.
Cytogenetic and obstetric services at a tertiary referral centre, Copenhagen.
Time necessary to complete the test. Proportion of cell nuclei containing two and three hybridisation signals in karyotypically normal and abnormal amniotic fluid samples.
The test could be completed within three to four days after amniocentesis. In the normal samples a mean of 73% (range 61-82%) of the amniotic cell nuclei showed two hybridisation signals and 6% (0-18%) showed three signals. By contrast, among the trisomic samples 29% (19-38%) of the nuclei exhibited two signals and 48% (31-60%) showed three signals.
The technique clearly distinguished between normal and trisomic samples. Prenatal diagnosis with in situ hybridisation with chromosome specific probes was fast and may make it possible to screen for selected, aneuploidies. However, the technique is still at a preliminary stage and needs further evaluation and refinement.
设计并评估一种用于检测未培养羊水细胞样本中21三体（唐氏综合征）的快速筛查方法。
使用HY128进行非放射性原位杂交，HY128是一种针对21号染色体的50万个碱基对的酵母人工染色体探针。对12份核型正常的羊水样本和8份21号染色体三体样本进行盲法研究。
哥本哈根一家三级转诊中心的细胞遗传学和产科服务部门。
完成检测所需的时间。核型正常和异常羊水样本中含有两个和三个杂交信号的细胞核比例。
羊膜腔穿刺术后三到四天内即可完成检测。在正常样本中，平均73%（范围61%-82%）的羊水细胞核显示两个杂交信号，6%（0%-18%）显示三个信号。相比之下，在三体样本中，29%（19%-38%）的细胞核显示两个信号，48%（31%-60%）显示三个信号。
该技术能明确区分正常样本和三体样本。用染色体特异性探针进行原位杂交的产前诊断速度快，可能使筛选特定的非整倍体成为可能。然而，该技术仍处于初步阶段，需要进一步评估和完善。
