Single molecule sequencing: gene sequencing is no longer out of reach
At the beginning of J. P. Morgan health care meeting, the gene sequencing Illumina announced that will create a new company, grail, working to develop a no more than $1000 a blood test for early screening of many types of cancer. The main purpose of this tumor DNA sequencing is to diagnose a wide variety of cancers in asymptomatic individuals, and to achieve early prevention or treatment.
As technology continues to progress, the cost of gene sequencing is becoming increasingly close to the people". However, people believe that $1000 still can not make the gene sequencing into a flying into the common people's clinical diagnosis price, people's next goal is $100.
"If the next generation sequencing mission is to make the cost down to $1000 / genome, then three generation sequencing mission is to keep costs down to $100 / genome, to further promote the development of sequencing for routine clinical detection technology, in the clinical diagnosis and treatment of play greater role." Associate professor of South China University of science and technology, Shenzhen City Hanhai gene Biotechnology Co., Ltd. (hereinafter referred to as "Hanhai gene") he Jiankui, founder and CEO, told the China Science News "reporter, with the third generation sequencing technology (i.e.," single molecule sequencing technology) development, people from close to the target is closer and closer.
The third generation sequencing is more easy to clinical promotion
In the world, gene sequencing was once a few companies monopoly, the famous sequencing company has Life, Tech Roche, Illumina, Pacific biological, etc., more than 99% of our country's sequencing instruments and reagents are dependent on imports. But in the single molecule sequencing, after only the United States and the United Kingdom launched the third generation sequencing.
"The industry is very concerned about the third generation sequencing. Pacific biological in 2014 launched a miniaturized single molecule sequencing Sequel, in just one month's time, their company's share price has doubled." Hanhai gene chemistry department director Gao Yan said that in clinical application, the third generation sequencing has a advantage of greater than the second generation sequencing.
"Second generation sequencing need a complex of sample preparation process, at the same time in order to database, need to match more than 10 sets of equipment, light these devices will need more than one million yuan." Gao Yan told the China Science News reporter, the two generation sequencing technology is difficult to promote in the hospital. Physicians are reluctant to cumbersome, relative professional level of sample preparation operation, they expect one button, automation instrumentation: tested sample inside, automatic operation, the next day has been a very direct report, rather than the sequencing results from the third party of the biological information science professionals were analyzed, and then back to the doctor.
He Jiankui believes that compared to the second generation sequencing, the application of the third generation of sequencing technology in clinical has obvious advantages: the third generation sequencing technology without the need for PCR amplification and sequencing can be directly performed on a single molecule; sample preparation is simple, the cost of sequencing further reduced; can be directly read RNA sequence and including methylation, DNA modification. These advantages can greatly improve the cost, speed and quality of clinical gene sequencing.
Precise medical entrance
Gene sequencing, as an important part of precision medical treatment, has developed rapidly in recent years with the progress of technology and the decline of cost.
Precision medical mainly consists of two parts, precision diagnosis and precision treatment. As the key to accurate diagnosis, gene sequencing has become a truly accurate medical entrance. Today, medical departments through gene sequencing and analysis the molecular level on patient information was collected, using bioinformatics analysis tools to integrate and analyze all the information, the doctor can early predict disease occurrence, the possible direction of development and disease can, to help diagnosis is made.
He Jiankui said that at present, the single molecule sequencing platform can be widely used in a prenatal diagnosis, tumor in early stage without a diagnosis, preimplantation genetic screening, detection of pathogens and genetic disease gene mutation detection.
It has been reported in the literature that screening for Down's syndrome, single molecule sequencing technology is more sensitive than Illumina sequencing technology to detect chromosome 21." Gao Yan told reporters that their experimental design also shows that single molecule sequencing can detect 3% of the low frequency mutation.
For patients with cancer, if the tumor is resected, only 40% of them are true cancer tissues, and the remaining 60% are normal blood vessels and other tissues. In 40% of the cancer tissues, only 50% of the cancer had a mutation, and the other half were normal. In this way, the mutant cancer cells that need to be truly detected only account for about 20% of the cancer tissue that is going to be removed.
"Our team will target gene capture and sequencing in one step, to achieve a single molecule targeted sequencing. After the experimental design, it is proved that the 3% low frequency mutation can be detected. Therefore, we believe that this principle may be used in the future cancer early detection." Gao Yan said.
In addition, he Jiankui told reporters, for such as Ebola major outbreaks of infectious disease applications, the application of the third or the fourth generation (nano pore molecular sequencing) sequencing technology is to first time for virus prototype, so as to provide a scientific basis for the prevention and control of major infectious diseases.
"Sequencing technology can not only be used for scientific research, but also for clinical use, so that it will have a broader market and a more long-term life.