The invention relates to a method for enriching a target polynucleotide sequence containing a genetic variation said method comprising: (a) providing two primers targeted to said target polynucleotide sequence; (b) providing a target specific xenonucleic acid clamp oligomer specific for a wildtype polynucleotide sequence; (c) generating multiple amplicons using PCR under specific temperature cycling conditions; and (d) detecting said amplicons. We introduce a novel molecule, Xenonucleic Acid (XNA) for the NGS library preparation. XNA is able to selectively suppress amplification of DNA with wild type alleles and amplify DNA containing mutant alleles. Mutants with low allelic frequency will be easily detectable without deep sequencing after enrichment by adding XNA in multiplex PCR. The 17 actionable mutants related to lung or colorectal cancer diseases at different variant allelic frequency (VAF) % were investigated. Clinical sensitivity is significantly improved with XNA in various types of samples.
本发明涉及一种富集含有遗传变异的目标多核苷酸序列的方法,所述方法包括:(a) 提供针对所述目标多核苷酸序列的两个引物;(b) 提供针对野生型多核苷酸序列的目标特异性异种核酸钳夹寡聚体;(c) 在特定温度循环条件下使用 PCR 生成多个扩增子;以及 (d) 检测所述扩增子。我们为 NGS 文库制备引入了一种新型分子--Xenonucleic Acid(XNA)。XNA 能够选择性地抑制野生型等位
基因 DNA 的扩增,而扩增含有突变等位
基因的 DNA。在多重 PCR 中加入 XNA 进行富集后,等位
基因频率较低的突变体无需深度测序即可轻松检测到。我们研究了与肺癌或结直肠癌疾病相关的 17 种可操作突变体,其变异等位
基因频率(VAF)各不相同。在各种类型的样本中,使用 XNA 可明显提高临床灵敏度。