Single-nucleotide variants (SNVs) that are strongly associated with many genetic diseases and tumors are important both biologically and clinically. Detection of SNVs holds great potential for disease diagnosis and prognosis. Recent advances in DNA nanotechnology have offered numerous principles and strategies amenable to the detection and quantification of SNVs with high sensitivity, specificity, and programmability. In this review, we will focus our discussion on emerging techniques making use of DNA strand displacement, a basic building block in dynamic DNA nanotechnology. Based on their operation principles, we classify current SNV detection methods into three main categories, including strategies using toehold-mediated strand displacement reactions, toehold-exchange reactions, and enzyme-mediated strand displacement reactions. These detection methods discriminate SNVs from their wild-type counterparts through subtle differences in thermodynamics, kinetics, or response to enzymatic manipulation. The remarkable programmability of dynamic DNA nanotechnology also allows the predictable design and flexible operation of diverse strand displacement probes and/or primers. Here, we offer a systematic survey of current strategies, with an emphasis on the molecular mechanisms and their applicability to in vitro diagnostics.

中文翻译：

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DNA链置换反应：区分单个核苷酸变异的强大工具。

与许多遗传疾病和肿瘤密切相关的单核苷酸变体（SNV）在生物学和临床上都很重要。SNV的检测在疾病诊断和预后方面具有巨大潜力。DNA纳米技术的最新进展提供了许多适用于以高灵敏度，特异性和可编程性检测和定量SNV的原理和策略。在这篇综述中，我们将集中讨论利用DNA链置换（动态DNA纳米技术的基本组成部分）的新兴技术。基于它们的操作原理，我们将当前的SNV检测方法分为三个主要类别，包括使用脚趾介导的链置换反应，脚趾交换反应和酶介导的链置换反应的策略。这些检测方法通过热力学，动力学或对酶操作的响应之间的细微差别将SNV与野生型对应物区分开。动态DNA纳米技术的卓越可编程性还允许各种链置换探针和/或引物的可预测设计和灵活操作。在这里，我们提供了对当前策略的系统综述，重点是分子机制及其在体外诊断中的适用性。