应用PCR-STR分型技术快速产前基因诊断Down综合征

The application of PCR-STR typing technology to rapid prenatal diagnosis of Down syndrome

目的 探讨应用PCR -STR分型技术 ,快速产前基因诊断Down综合征 (Downsyndrome ,DS)方法。方法 选择 2 1号染色体上的 4个短串联重复序列D2 1S2 0 5 5、D2 1S12 4 4、D2 1S14 35和D2 1S180 9,进行PCR扩增 ,尿素非变性聚丙烯酰胺凝胶电泳 ,银染分型。根据谱带的条数及浓度判断是否为 2 1三体 ,根据父母基因型判断额外 2 1号染色体的亲代来源 ,选择30例高危孕妇进行 2 1三体的产前基因诊断。结果 应用此方法可检出所有的由核型分析确诊的单纯型 2 1三体 ,并可判定额外染色体的亲代来源。 30例产前诊断筛出 2例 2 1三体患儿。结论 该方法不用细胞培养 ,避免放射性标记 ,并可进行早期产前诊断。该方法比传统的方法操作简单、速度快 ,是一种产前诊断和大规模筛查 2 1三体的良好的方法。

Objective: To reseach the the application of PCR-STR typing technology to rapid prenatal diagnosis of Down syndrome. Methods: We collected DNA from 30 amniotic fluid both parets and patient and used polymerase chain reaction to amplify four specific sequence on chromosome 21: D21S2055、D21S1244、D21S1435和D21S1809. The amplified products were analyzed using the PAGE eletrophoresis and silver staining to determine the 21 trisomy and origin of the extra chromosome 21. Results: All of the complete trisomy 21 were detected by this method;the parental source of extra chromosome 21 was easily determined.Among 30 amniotic fluid samplings,2 were positive .Conclusions: This method need not cell educates,avoiding the radio marking and can proceed the prenatal diagnosis of the earlier period. The method is more simple and rapid than traditional method operation,is a good method that a kind of prenatal and check with large-scale chromosome 21.