Abstract:
Whole-genome bisulfite sequencing (WGBS) enables the detection of DNA methylation at a single base-pair resolution. The treatment of DNA with sodium bisulfite allows the discrimination of methylated and unmethylated cytosines, but the power of this technology can be limited by the input amounts of DNA and the length of DNA fragments due to DNA damage caused by the desulfonation process. Here, we describe a WGBS library preparation protocol that minimizes the loss and damage of DNA, generating high-quality libraries amplified with fewer polymerase chain reaction (PCR) cycles, and hence data with fewer PCR duplicates, from lower amounts of input material. Briefly, genomic DNA is sheared, end-repaired, 3\'-adenylated, and ligated to adaptors with fewer clean-up steps in between, minimizing DNA loss. The adapter-ligated DNA is then treated with sodium bisulfite and amplified with a few PCR cycles to reach the yield needed for sequencing.
摘要:
全基因组亚硫酸氢盐测序(WGBS)能够以单碱基对分辨率检测DNA甲基化。用亚硫酸氢钠处理DNA可以区分甲基化和未甲基化的胞嘧啶,但这项技术的力量可能会受到DNA输入量和DNA片段长度的限制,因为脱磺化过程造成的DNA损伤。这里,我们描述了一个WGBS文库制备方案,最大限度地减少DNA的损失和损伤,生成用较少的聚合酶链反应(PCR)循环扩增的高质量文库,因此,PCR重复的数据较少,来自较低数量的输入材料。简而言之,基因组DNA被剪切,末端修复,3\'-腺苷酸化,并连接到适配器上,其间清理步骤较少,减少DNA丢失。然后用亚硫酸氢钠处理衔接子连接的DNA,并用几个PCR循环扩增以达到测序所需的产率。