Research and Development, Cytogenetics and Molecular Biology, TOMA Advanced Biomedical Assays, Busto Arsizio, Varese, Italy.
Prenat Diagn. 2013 Jan;33(1):32-41. doi: 10.1002/pd.4004. Epub 2012 Nov 20.
Karyotyping is a well-established method of investigating the genetic content of product of conceptions (POCs). Because of the high rate of culture failure and maternal cell contamination, failed results or 46,XX findings are often obtained. Different molecular approaches that are not culture dependent have been proposed to circumvent these limits. On the basis of the robust experience previously obtained with bacterial artificial chromosomes (BACs)-on-Beads™ (BoBs™), we evaluated the same technology that we had used for the analysis of prenatal samples on POCs.
KaryoLite™ BoBs™ includes 91 beads, each of which is conjugated with a composite of multiple neighboring BACs according to the hg19 assembly. It quantifies proximal and terminal regions of each chromosome arm. The study included 376 samples.
The failure rate was 2%, and reproducibility >99%; false-positive and false-negative rates were <1% for non-mosaic aneuploidies and imbalances effecting all three BACs in a contig. Detection rate for partial terminal imbalances was 65.5%. The mosaic detection threshold was 50%, and the success rate in macerated samples was 87.8%. The aneuploidy detection rate in samples with cell growth failure was 27.8%, and maternal cell contamination was suspected in 23.1% of 46,XX cultured cells.
KaryoLite™ BoBs™ as a 'first-tier' test in combination with other approaches showed beneficial, cost-effective and clearly enhanced POC testing.
核型分析是一种研究胚胎产物（POC）遗传内容的成熟方法。由于培养失败和母体细胞污染率高，经常获得失败结果或 46,XX 发现。已经提出了不同的非培养依赖的分子方法来规避这些限制。基于之前使用细菌人工染色体（BAC）-on-Beads™（BoBs™）获得的可靠经验，我们评估了我们之前用于产前样本分析的相同技术在 POC 上的应用。
KaryoLite™BoBs™ 包含 91 个珠子，每个珠子都根据 hg19 组装与多个相邻 BAC 的复合物连接。它定量了每条染色体臂的近端和末端区域。该研究包括 376 个样本。
失败率为 2%，重复性>99%；非嵌合性非整倍体和影响连续体中所有三个 BAC 的不平衡的假阳性和假阴性率<1%。部分末端不平衡的检测率为 65.5%。镶嵌检测阈值为 50%，在粉碎样本中的成功率为 87.8%。在细胞生长失败的样本中，非整倍体的检测率为 27.8%，在培养的 46,XX 细胞中，有 23.1%怀疑存在母体细胞污染。
KaryoLite™BoBs™ 作为一种“一线”测试，与其他方法结合使用，显示出有益、具有成本效益且明显增强了 POC 测试。
