The discovery of circulating fetal DNA in the plasma of pregnant women has greatly promoted advances in noninvasive prenatal testing. Screening performance is enhanced with higher fetal fraction and analysis of samples whose fetal DNA fraction is lower than 4% are unreliable. Although current approaches to fetal fraction measurement are accurate, most of them are expensive and time consuming. Here we present a simple and cost-effective solution that provides a quick and reasonably accurate fetal fraction by directly evaluating the size distribution of circulating DNA fragments in the extracted maternal cell-free DNA. The presented approach could be useful in the presequencing stage of noninvasive prenatal testing to evaluate whether the sample is suitable for the test or a repeat blood draw is recommended.

中文翻译：

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基于母体游离 DNA 的直接大小分布分析的胎儿分数预测在线工具。

孕妇血浆中循环胎儿DNA的发现极大地促进了无创产前检测的进步。较高的胎儿分数可增强筛查性能，并且对胎儿 DNA 分数低于 4% 的样本进行分析是不可靠的。尽管目前的胎儿分数测量方法是准确的，但大多数方法既昂贵又耗时。在这里，我们提出了一种简单且经济高效的解决方案，通过直接评估提取的母体无细胞 DNA 中循环 DNA 片段的大小分布，提供快速且合理准确的胎儿分数。所提出的方法可用于无创产前检测的预测序阶段，以评估样本是否适合检测或建议重复抽血。