To prepare samples for next generation sequencing (NGS), they must be transformed and collected into libraries. The main types of library prep are ligation and tagmentation. Ligation-based library prep can be enzymatic or physical. Preparing quality libraries opens the door to discovery through a variety of NGS-based applications.
Before DNA or RNA samples can be sequenced, they must be fragmented, end-repaired, and ligated to sequencing adapters. Library preparation protocols can influence the results generated by your next generation sequencing data. The major steps of ligation-based library preparation are pictured below (Figure 1) and summarized as follows:
Fragmenting shears the samples into pieces of DNA of a desired length. Typically, whole genome sequencing works best with 350 bp fragments, and hybridization capture works best with 200 bp fragments.
There are 2 main methods of fragmentation for ligation-based DNA library prep:
Tagmentation is an alternative protocol that combines the fragmentation and adapter ligation steps. Some versions of this protocol could introduce a coverage bias that, depending on experimental design, may impact sequencing results.
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The Lotus DNA Library Prep Kit enables streamlined preparation of high-quality next generation sequencing (NGS) libraries from double-stranded DNA (dsDNA)—generate libraries suitable for PCR-free, PCR-amplified, and targeted sequencing applications on Illumina platforms.
The xGen Prism DNA Library Prep Kit empowers you with sensitive and accurate variant detection from degraded samples, such as cell-free DNA (cfDNA) or formalin-fixed, paraffin-embedded (FFPE) samples. The kit’s proprietary ligation strategy maximizes conversion and virtually eliminates adapter-dimer formation. The unique molecular identifier (UMI) sequences incorporated during single-stranded ligation enable a variety of deduplication and error correction strategies.
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