Lebo R V, Flandermeyer R R, Diukman R, Lynch E D, Lepercq J A, Golbus M S
Department of Obstetrics, University of California, San Francisco.
Am J Med Genet. 1992 Jul 15;43(5):848-54. doi: 10.1002/ajmg.1320430519.
We have used chromosome-specific repetitive sequences to detect the most common human aneuploidies prenatally. Together chromosome 21, 13, 18, X, and Y aneuploidy comprises 95% of the chromosome abnormalities that result in a high risk of abnormal phenotypes at birth. The X, Y, and 18 repetitive probes work reliably in multiple tissue types including directly examined and cultured amniocytes, chorionic villus cells, lymphocytes, and cultured fibroblasts. The probe that detects both chromosomes 13 and 21 routinely gives results in each cell type tested except directly studied amniocytes which can be interpreted in seven-ninths of the cases with protocol 1 and all tested samples with protocol 2. Our protocols diagnosed trisomy 21 in a 23-week fetus with low maternal serum AFP and a trisomy 18 in a direct chorionic villus sample 2 working days after the samples were obtained. Trisomy 21 also has been ruled out in a CVS karyotype first thought to be 47,XY, +21. These studies reflect the potential value of in situ hybridization to provide a more rapid, less expensive means to screen most at-risk fetal populations with less effort in first world cytogenetic laboratories, and to provide economical cytogenetic services in less developed countries.
我们已使用染色体特异性重复序列对最常见的人类非整倍体进行产前检测。21号、13号、18号染色体以及X、Y染色体的非整倍体共同构成了95%的染色体异常情况，这些异常会导致出生时出现异常表型的高风险。X、Y和18号重复探针在多种组织类型中均能可靠发挥作用，包括直接检测的羊水细胞、绒毛膜绒毛细胞、淋巴细胞和培养的成纤维细胞。用于检测13号和21号染色体的探针在除直接检测的羊水细胞外的每种检测细胞类型中都能常规得出结果，对于直接检测的羊水细胞，方案1能在九分之七的病例中进行解读，方案2能对所有检测样本进行解读。我们的方案在样本获取后2个工作日，诊断出一名23周胎儿为21三体（其母血清甲胎蛋白水平低），并在一份直接绒毛膜绒毛样本中诊断出18三体。在最初被认为是47,XY, +21的绒毛取样核型中也排除了21三体。这些研究反映了原位杂交的潜在价值，即它能提供一种更快速、成本更低的方法，在第一世界的细胞遗传学实验室中，以更少的精力筛查大多数高危胎儿群体，并在欠发达国家提供经济实惠的细胞遗传学服务。
