比较基因组杂交技术的改进及其在产前诊断中的应用

目的改进比较基因组杂交（CGH）技术，为产前诊断胎儿染色体异常提供有益手段。方法选取唐氏综合征筛查结果为高风险、细胞遗传学结果异常的孕妇5例，因胎儿畸形、死胎引产的孕妇11例。缺口平移法标记待测DNA和对照DNA，同时将待测DNA和对照DNA的荧光颜色互换，即进行荧光互换CGH，根据绿红两种信号的比值制作CGH拷贝数核型模式图，以1.0表示平衡比例，荧光强度比（FR）阈值定为1.25和0.75。以细胞遗传学检查检验CGH分析的敏感性和可靠性。结果16例孕妇胎儿样本均成功利用CGH方法进行了分析、确认，结果与细胞遗传学分析一致；1例细胞遗传学诊断为4号染色体的长臂远端部分缺失病例，CGH为4号染色体q32 qter缺失。CGH分析在荧光互换前后FR曲线并不完全互补。结论CGH技术经荧光互换等改进能最大程度的排除在实验过程中可能产生的误差，可作为产前诊断中传统核型分析的有益和必要补充。

Improvement and application of comparative genomic hybridization in prenatal diagnosis

Objective To create a useful comparative genomic hybridization(CGH) for prenatal diagnosis.Methods 5 pregnancies with abnormal cytogenetic results and 11 pregnancies with malformed infants were enrolled in this study.Sample DNA and control DNA were labeled with Spectrum Green dUTP and SpectrumRed dUTP respectively using the nick translation kit.Simultaneously,fluorochrome-exchanged CGH was designed.Sample DNA was labeled with SpectrumRed dUTP and genomic DNA was labeled with SpectrumGreen.The karyotyping wa...