The novel corona passage virus epidemic has resulted in the common people understanding that "nucleic acid detection" technology can quickly and economically detect whether a person has been infected with the novel coronavirus. And this is just a microcosm of the newer iterations of pathogen detection technology.

With the accumulation of data and the development of technology, the application of high-throughput sequencing technology in clinical pathogen detection, epidemiologic investigation and other aspects has become increasingly mature. The mNGS detection method, based on all nucleic acid sequencing, has progressively manifested greater advantages in clinical detection and the discovery of new epidemiological pathogens. mNGS can be used to detect pathogens in the samples unbiasedly, as long as pathogens reaching a certain abundance, while the detection of low-abundant pathogens is not effective (the detection lacks the required sensitivity). In order to achieve sufficient sequencing saturation, the sequencing data volume of 20M reads is commonly used in clinical practice, which makes the detection cost of single samples high. Pathogen detection based on targeted capture can perfectly compensate for these shortcomings.

 

	mNGS	tNGS(capture probes or ultra-multiplex PCR)）
Detection range	No limit, acceptable beyond detection limit	Only pathogens designed with probes/primers can be detected, usually tens to hundreds
Turn around time	24h	24h
Sensitivity	General	Very high
Test fee	Comparatively high	Comparatively low

Table 1 Comparison of mNGS and tNGS .

 

Targeted capture based pathogen detection (targeted NGS, tNGS, targeted capture and ultra-multiplex PCR) allows for the designing of specific probes and primers according to the sequences of determined pathogenic species, which enriches the pathogenic sequences in the extracted nucleic acids and then sequences them. After the enrichment of nucleic acids, there is a significant reduction in human source background, and the proportion of pathogenic sequences increases from single digits to more than 90%, which can significantly improve detection sensitivity while greatly reducing the amount of sequencing data and analysis workload. Using a rapid library preparation solution, a turn around time similar to that of mNGS can be obtained, which greatly meets the needs of a large number of sample tests such as those in clinical use and epidemiologic investigation.

Figure 1 I Comparison the performance of mNGS and ultra-multiplex PCR enrichment (NZ4003A) for two samples. The vertical axis is the proportion of sequences, and the enrichment effect is clearly evident.

Figure 2 I Comparison of performance using mNGS and liquid phase hybrid capture respectively (NY1023A). Different samples showed enrichment ranging from 10-90X.

 

Dynegene Technologies is the first company in China which have the ability to independently synthesize oligo pools at high throughput. Based on oligo pool synthesis, liquid probe hybridization capture and multiplex PCR were developed for targeted sequencing. Combined with the company's self-developed algorithm, in consideration of the more genomic variation of pathogenic species, conserved regions within the species are selected and specific primers or probes are designed, which allows for the development of detection products specifically enriched for pathogens. Combined with DNA and RNA co-preparation library products, the DNA and RNA sequences of pathogens can be detected simultaneously. Aimed at different detection ranges and sample conditions, multiplex amplicon and probe hybridization capture have their own focal points and advantages, and Dynegene is in a position to provide suggestions according to specific circumstances to help customers develop the most suitable detection solution.

 

For the respiratory passage, 76 pathogen detection products and new coronavirus detection products have been available. We warmly welcome you to contact us for consultation and purchase of our existing products, but you also have the option to develop customize your own pathogen detection products according to your individual needs.

Item No.	Product Name	Format	Description
NY1021A	QuarXeq coVID-19 Virus Probes	96rxn	Whole genome sequence capture of the novel coronavirus
NY1023A	QuarXeq Respiratory Pathogens Probes	96rxn	Capture probes for 76 respiratory pathogens
NZ4003A	QuarMultiple Respiratory Pathogens Amplicon	96rxn	Multiplex primers for 76 respiratory pathogens
NK3002A	QuarPlex 16S rDNA Kit	96rxn	116S rDNA assay kit V3-V4

Table 2 List of Dynegene products related to pathogen detection