State-of-the-art nanotechnology for rapid and accurate processing of genetic information

Early in the 21st century, humans succeeded in decoding the human genome. Since then, research institutes, medical and information technology companies in Japan, Europe, and the US have been involved in fierce competition to develop a method to rapidly, accurately, and inexpensively decode genetic information. Meanwhile, a group of researchers led by KAWAI Tomoji , Specially Appointed Professor, Institute of Scientific and Industrial Research at Osaka University, succeeded, in a world first, in decoding DNA and RNA genetic information using a gating nanopore device.

What is a gating nanopore device and how does it work sequencing technology?

A nanopore is a small hole 1 nanometer in diameter. DNA can be sequenced by threading it through such a pore. The information stored in DNA as a code is made up of four chemical bases: adenine, thymine, guanine, and cytosine. Human DNA consists of about 3 billion bases. When these base molecules of DNA go through a nanopore, an electric current flows between the nano electrodes in the nanopore. The electric current varies according to the base passing through. DNA sequencing is thereby achieved by measuring the variations in the electric current. When gates are placed at the nanopore, it is called a gating nanopore.

Compared with conventional methods, what specific progress has been achieved in sequencing techonogy by using gating nanopore methods?

PCR (Polymerase Chain Reaction) is a widely used conventional method. This method copies segments of DNA in order to decode the genome. Therefore, this method requires a lot of DNA replication so it is time-consuming and requires special reagents as well. However, in nanopore technology, only one DNA is necessary and DNA replication is not needed. The decoding speed is one micro second (a millisecond) for a single base. Even human DNA consisting of about 3 billion bases can be decoded within a day if it is sequenced using multiple machineries at the same time. Moreover, special reagents are not needed so that cost can be reduced.

World first DNA sequencing using nanopore technology

When did you start working on DNA sequencing by gating nanopore technology?

I started DNA sequencing using electricity around 1994. At that time, it was said that DNA sequencing using electricity was possible in theory but impossible in practice. 15 years later, in 2009, we succeeded in an experiment that proved using a nanopore possible using a scanning tunneling microscope. Our group cleared the way for DNA sequencing technology by making use of a gating nanopore for the first time in the world. At that time, in order to develop countermeasures against virulent viruses and provide individual patient with optimal care, there was a great social need for developing technology in order to decode a genome within a day for $1,000. Under such circumstance, the National Institutes of Health (NIH) in the USA announced that nanopore technology would be a leading candidate for the $1,000 decoding of the human genome within a day. That was a year before the publication of the results of my experiment proving such possible, a technology that had been widely expected.

This technology attracting international attention has a lot of rivals

Wasn't DNA sequencing technology using a gating nanopore the first stage in the achievement of the $1,000 Genome?

In the same year that I succeeded in my experiment that proved it possible, my project was selected as a Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST). This project was a large-scale project in cooperation with companies and other universities. The fund from FIRST added momentum to my research. However, nanopore technology continues to attract international attention and there are many competitors. With financial aid from the NIH, Harvard University and the University of California in the US and the University of Oxford and other universities in Europe and the US, information technology companies such as IBM and Intel Corporation are involved in DNA sequencing technology as well. Also, China which had not been moving at all, has begun to move, introducing technology from the US and other countries and starting up research institutes.

What is the strength of the Kawai Lab countering international competitors?

First of all, our lab is the technological leader in the development of the technology behind gating nanopores. We are far ahead of other institutes and we have excellent staff members. Facilities and equipment are needed for research, but it is the persons who conduct the research.

A technology for carrying one's own genome

What drives you?

Enthusiasm for being at the cutting edge and a sense of fulfillment when I have achieved something drives me. We face many challenges, but I feel proud to be carving out a path in a new field and continuing to create a path. Furthermore, we also aggressively promote research on campus as well as through university-industry collaboration.

For example, in joint research with Toray Industries Inc., we are developing technology leading to early detection of cancer based on analysis of RNA in the blood. In joint research with Toshiba Corporation, we are addressing high-speed analysis of new types of viruses. This joint research with Toshiba contributes to the acceleration of early detection of new viruses and vaccine development. Putting our technology to use gives further momentum to our research.

This is a project that will contribute to enhancing the quality of life in medical care, isn't it?

In advanced medical care, the primary idea is to maintain and improve quality of life in three steps: early disease detection, improvement of therapeutic techniques, and enhancement of regenerative medicine. In these three steps, I think early disease detection is most important because hospitalization and surgery are not needed. As a use in genetic analysis by nanopore technology, I'm thinking of, for example, installing a small device on a smartphone in order to store the phone user's DNA sequence data. Examinations for disease sometimes require blood test requiring injection or hospitalization. They are often time-consuming and painful. However, ultra small genetic analysis technology enables one to use a cotton swab to get cells from the oral membrane at one's family clinic or at home, get one's genetic information and the newest health conditions within a day. In this way, if we update our health information network, we can know more about our body and early disease detection becomes possible.

As the Apollo program realized a great dream in landing a man on the moon promoted the progress of science and technology in the 1960s, I believe that this nanopore technology will be a driving force for making our life better.