Domestic production is rising! Industrial Chain Diagram and Market Analysis of Gene Sequencing in China
Industrial information? Flint creation? 2022.07. 13? 1 180
Gene sequencing technology is one of the key technologies of gene detection, which is widely used in scientific research, clinical application and other fields. After nearly 50 years of development, gene sequencing technology has developed from the first generation Sanger technology to the fourth generation nanopore sequencing technology, among which the second generation NGS technology is the most widely used gene sequencing technology in the market at present, and the third and fourth generation sequencing technologies are still in the initial stage of development. The gene sequencer market is basically monopolized by multinational giants, and Chinese gene sequencing manufacturers mainly arrange matching reagents for the sequencer. With the continuous research and innovation of domestic enterprises, a number of self-developed gene sequencer products are gradually approved for listing. In terms of market application, China's non-invasive prenatal genetic testing (NIPT) market has developed steadily; With the promotion of national policies and technological progress, tumor gene diagnosis and early screening are expected to become one of the most promising application markets for gene sequencing.
First, the definition and technology of gene sequencing
(A) the definition of gene sequencing
Gene sequencing is a new gene detection technology, which can analyze and determine the whole gene sequence from blood or saliva, predict the possibility of suffering from various diseases, and the behavior characteristics and behaviors of individuals are reasonable. Gene sequencing technology can lock individual pathological genes and prevent and treat them in advance. Gene sequencing related products and technologies have developed from laboratory research to clinical application. It can be said that gene sequencing technology is the next technology to change the world.
(2) Gene sequencing technology
From 1975, Sanger and Coulson invented chain termination method and 1976- 1977, maxam and Gilbert invented chemical degradation method to 1986, ABI successfully commercialized the first generation gene sequencing technology for the first time.
1, the first generation of gene sequencing technology (Sanger)
Core principle: Because the 3' position of dideoxynucleoside triphosphate (ddNTP) does not contain hydroxyl group, it can not form phosphodiester bond during DNA synthesis, so it can be used to interrupt DNA synthesis reaction. A certain proportion of radioisotope-labeled DD NTP(ddtp, ddCTP, ddGTP, ddTTP) was added to the four DNA synthesis reaction systems to generate a series of nucleotides with different lengths of A, T, C and G4, and then the DNA sequence of the molecule to be detected can be determined by gel electrophoresis and autoradiography according to the position of the electrophoresis band.
The traditional first-generation gene sequencing technology has the advantages of high accuracy, simplicity and rapidity, but it also has some limitations: 1) The sequencing throughput is low, and it is only suitable for the identification of small samples of genetic diseases, and it is difficult to complete the screening of large samples with no clear candidate genes or a large number of candidate genes; 2) Sequencing is costly and time-consuming. It is estimated that it will take at least three years and cost $3 billion to complete the whole human genome sequencing by this method. Therefore, the first generation of gene detection technology is mostly used in scientific research. With the development of science and technology, the second generation sequencing technology with high Qualcomm capacity, low cost and high degree of automation has emerged.
2. The second generation gene sequencing technology (NGS)
The second-generation gene sequencing technology uses a series of high-throughput sequencing techniques to sequence large-scale genomic DNA or RNA, which can quickly and accurately obtain the genome coding sequence in a very short time and meet the requirements of high-resolution detection of genome. High-throughput sequencing technology is a revolutionary change of traditional sequencing technology, also known as Next Generation Sequencing (NGS).
Core principle: With the help of fluorescent or chemiluminescent substances, the sequence of DNA or RNA can be determined indirectly by reading the optical signals released in the process of connecting bases to DNA chains by DNA polymerase or DNA ligase. Compared with the first-generation gene sequencing technology, NGS sequencing technology greatly reduces the time and cost of sequencing, solves the pain point of low Qualcomm and high cost of the first-generation technology, and makes gene sequencing realize large-scale commercial application, which is the mainstream technology in the global and national markets. At present, the cost of sequencing a single human genome has dropped below $65,438+$0,000.
NGS sequencing technology has many advantages, such as a large number of Qualcomm, low cost and strong ability to detect high and low abundance DNA, but it also has the following disadvantages: 1) reading length. The maximum reading length of each DNA fragment in the second generation sequencing technology is about 400-700bp, which is much lower than 900- 1000bp in the first generation sequencing. 2) The sequencing results are difficult to process. Because the reading length of the second-generation sequencing is greatly shortened, the overlapping area between two DNA fragments is also reduced accordingly, which makes the splicing of sequencing results more difficult. In addition, due to the Qualcomm amount of the second generation sequencing, it is more difficult to process the sequencing results. In order to solve these problems, the third generation sequencing technology marked by single molecule sequencing and the fourth generation sequencing technology represented by nanopore sequencing came into being.
3. The third generation gene sequencing technology (single molecule sequencing)
The third generation sequencing (TGS) refers to sequencing the genome at the level of single cell and single molecule, and PCR amplification is not needed in the sequencing process, so that each DNA molecule can be sequenced independently. It mainly includes Helico Bioscience's single molecule sequencing technology and Pacific Bioscience's single molecule real-time (SMRT) sequencing technology, with the latter as the representative.
Different from NGS sequencing technology, single-molecule sequencing technology can effectively obtain the complete sequence of a single RNA molecule with high quality by directly reading the reverse transcription full-length cDNA, so as to further study alternative splicing transcripts. Moreover, the sequencing process is relatively continuous, and the sequencing will not be suspended due to steps such as washing off reagents or detection, and DNA amplification is not needed, so that the operation is convenient and the sequencing time is short. Therefore, single molecule sequencing technology has the advantages of long reading time, short sequencing time and convenient operation. At present, this technology is still in the scientific research stage, and it will be widely used in clinic in the future as the technology matures.
4. The fourth generation gene sequencing technology (nanopore sequencing)
The fourth generation gene sequencing technology, also known as nanopore sequencing technology, is a technology based on electrical signal sequencing. The principle is that single-stranded nucleic acid molecules are driven by electric field force through nano-sized protein channels. Because different bases pass through the nanopore, current signals with different blocking degrees and blocking time are generated, so that the base information on each nucleic acid molecule can be identified according to the current signals, and the sequencing of single-stranded nucleic acid molecules can be realized.
Compared with single-molecule sequencing technology, nano-hole sequencing technology truly realizes the sequencing method combining single-molecule detection and electron conduction detection, completely gets rid of elution process and PCR amplification process, and has the advantages of long reading length, large Qualcomm, less sequencing time and simpler data analysis. Compared with the first and second generation sequencing technologies, the high error rate is the main disadvantage of nano-hole sequencing at present. At present, the nanopore sequencing platform on the market is mainly based on MinION nanopore sequencer of Oxford Nanopore Technology Company (ONT). The sequencing reading length of the sequencer is over 150kb, and it has the advantages of fast sequencing speed, real-time data monitoring and easy carrying. Nanopore sequencing technology is still in the initial stage of development, and the relatively mature application scenario is the detection of infectious pathogens.
Table 1: Comparison of four generations of gene sequencing technologies
Source: Flint creation is organized according to public information.
Second, the gene sequencing industry chain
The gene sequencing industry chain mainly includes manufacturers of gene sequencing equipment and supporting reagents such as upstream gene sequencer, midstream gene sequencing service providers and downstream suppliers.
Figure 1: Gene sequencing industry chain
Source: Flint's creation is based on public information
(1) Upstream: gene sequencing equipment manufacturers such as gene sequencer and supporting reagents.
Gene sequencer is one of the core links of gene sequencing industry chain, with high technical barriers, and its installed capacity is basically monopolized by multinational giants. At present, there are 20,000 gene sequencers installed in the world, among which the market share of Illumina is 80%, that of Thermo Fisher Scientific Shier is 9- 10%, and that of Illumina and Thermo Fisher Scientific Shier is almost 90%.
The gene sequencing instruments listed in China are mainly divided into three modes: independent research and development, OEM and cooperation with international giants. As of March 2022, there are 15 gene sequencer products that have been effectively approved for marketing through NMPA in China; Among them, 9 products were independently developed, mainly second-generation sequencers, and Huada Gene and Huada Manufacturing received the largest number of approvals, totaling 4. Domestic enterprises such as Qitan Technology, Zhenmai Bio-technology, Peacock Gene, Bispectral Diagnosis, and Jinshi Technology actively explore the layout of the third and fourth generation sequencers and related supporting reagents.
Due to the high technical barriers of gene sequencer, most domestic enterprises arrange sequencing reagents such as detection kits. Nearly 300 test kits have been effectively approved by NMPA to be listed in China, including more than 200 kits based on NGS technology, which is a rapidly growing part of the gene sequencing market. The independent research and development products of the third and fourth generation reagents are still in the initial stage of development, and the third and fourth generation sequencing instruments have not obtained the medical device registration certificate.