Nanopore sequencing technology (also known as fourth-generation sequencing technology) is a new generation of sequencing technology that has emerged in recent years. The current sequencing length can reach 150kb. This technology began in the 1990s and has undergone three major technological innovations: 1. Single-molecule DNA passes through the nanopore; Second, the enzyme on the nanopore controls the precision of the single molecule in the sequencing molecule; Sequencing precision control of glycosides. The widely accepted nanopore sequencing platform on the market is the MinION nanopore sequencer from Oxford Nanopore Technologies (ONT). It is characterized by single-molecule sequencing, long read sequencing (over 150kb), fast sequencing, real-time monitoring of sequencing data, and easy portability of the machine. This review focuses on the technical features and application areas of the MinION sequencer.
I. Introduction to MinION sequencing technology
The core of the MinION nanopore sequencer is a flow cell with 2,048 nanopores divided into 512 groups and controlled by an ASIC. The sequencing principle is shown in Figure 1a: First, the bimolecular DNA is linked to the lead adaptor (blue), the hairpin adaptor (red) and the trailing adaptor (brown); when sequencing begins, the lead adaptor leads the sequencing molecule into the nanopore controlled by the enzyme. After the lead adaptor is the template read (the DNA molecule to be sequenced) passes through the nanopore, the role of the hairpin adaptor is the guarantee of DNA double-strand sequencing, then the complement read (the complementary strand of the molecule to be sequenced) passes through the nanopore, and finally the trailing adaptor by. In the above sequencing method, template read and complement read pass through the nanopore in turn, using pairwise alignment, which combines into 2D read; in another sequencing method, without using hairpin adaptor, only template read is sequenced, and finally 1D read is formed. The latter sequencing method has a higher throughput, but the sequencing accuracy is lower than 2D read. Each adaptor sequence (adaptor) varies in current through the nanopore (Fig. 1c), and this difference can be used for base recognition.
Second, the advantages of MinION relative to other NGS sequencing platforms
1, the detection of base modification
Nanopore sequencing technology can detect four cytosine base modifications, 5-methycytosine, 5-hydroxymethycytosine, 5-formylcytosine and 5-carboxylcytosine. The detection accuracy is 92%-98%.
Lung Function Meter Filter,Medical Spirometry Filter,Spirometry Bacterial Filter,Disposable Lung Function Meter Filter
Hengshui Qifei Paper Products Co. LTD , https://www.hengshuiqifei.com