The technology relies on the fact that a DNA base, or a combination of bases on a DNA strand creates a characteristic disruption in a current as it passes through the nanopore. Electrodes measure the change in current flow as DNA molecules are fed through protein nanopores; an electrical gradient drives the DNA through the pore, while molecular "controllers" attached to the molecules mechanically slow them down so that their electrical signals may be recorded.
This approach has two important advantages.
First, the system is compact and doesn't require a supply of expensive reagents. That means sequencing can come out of the lab, making it useful for personalized medicine or for use in resource-poor clinics. Indeed, the disposable sequencer the company is about to introduce is the size of a USB memory stick.
Second, the technology reads much longer stretches of DNA than other rapid sequencing approaches, which means it has the potential to be better at spotting important "structural variants" related to disease. These variants occur when a whole segment of chromosome is moved, inverted, duplicated, or otherwise changed. When DNA is chopped into shorter stretches to be sequenced and then put back together on a computer, it is easier to miss, or misinterpret, such variants.
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