IN SITU HYBRIDIZATION IN PRENATAL DIAGNOSIS

该项目的目标是开发显著改进的自动化 检测最常见的细胞遗传学的技术 羊膜穿刺术或绒毛膜活检获得的间期细胞异常 绒毛取样(CVS)。在间期细胞上使用DNA探针可以避免 常规细胞遗传学分析所需的培养。这将减少 产前诊断的时间和费用以及允许延长检查的时间和费用 高危人群中的更大部分。自动化将是 尤其是当胎儿细胞可以从母体中分离出来时 血样。这将消除羊膜穿刺术或CVS的风险，并 将胎儿非整倍体筛查扩大到几乎所有怀孕。 我们将使用荧光DNA探针标记和自动图像分析 对间期21、18、13、X和Y染色体的数目进行量化 细胞。这五条染色体的非整倍体发生在大约2% 为“高龄产妇”进行的所有产前诊断测试，以及 占所有可存活的细胞遗传学异常的绝大多数 在羊膜穿刺术或CVS时观察。非整倍体快速筛查与性别鉴定 决心也将有助于涉及新生儿的情况 多发性先天性畸形或生殖器不明确，提示有可能 三体。通过原位杂交进行间期细胞分析可以提供 诊断不到24小时，而传统的诊断时间为48-72小时 对外周血进行细胞遗传学检查，羊水穿刺术需10-14天 或者是CVS。

The goal of this project is to develop significantly improved automated techniques for detecting the most commonly occurring cytogenetic abnormalities in interphase cells obtained by amniocentesis or chorionic villus sampling (CVS). Using DNA probes on interphase cells avoids the culturing required for routine cytogenetic analysis. This will reduce the time and cost of prenatal diagnosis and permit extension of the test to a larger segment of the at-risk population. Automation will be particularly important when fetal cells can be isolated from maternal blood samples. This would eliminate the risk of amniocentesis or CVS and extend fetal aneuploidy screening to virtually all pregnancies. We will use fluorescent DNA probe labeling and automated image analysis to quantify the numbers of chromosomes 21, 18, 13, X, and Y in interphase cells. Aneuploidies of these five chromosomes occur in approximately 2% of all prenatal diagnostic tests done for "advanced maternal age", and account for the great majority of all viable cytogenetic abnormalities observed at amniocentesis or CVS. Rapid aneuploidy screening and sex determination will also assist situations involving newborns with multiple congenital anomalies or ambiguous genitalia, suggesting possible trisomy. Interphase cell analysis by in situ hybridization could provide a diagnosis in under 24 hours, compared to 48-72 hours for conventional cytogenetics done on peripheral blood, and 10-14 days for amniocentesis or CVS.