The genome gadget

By Oliver Morton

As a gadget to plug into a USB port, the “MinION” recently unveiled by Oxford Nanopore lacks the touch-me buy-me pizazz of Jonathan Ive’s designs. And since it’s a prototype that no one outside the company and a few partner organisations has yet been able to see in action, it is hard to say how well it actually works. But as an embodiment of technological cool it strikes me as pretty much beyond compare.

Inside the MinION is a little chip with 512 holes in it. Put some DNA into the MinION, and it will pull individual DNA molecules through those pores. DNA molecules carry genetic information in the form of four different chemical bases, like slightly different knots on a piece of string. As a DNA molecule goes through one of the MinION’s pores, the different knots on it are sensed electronically; the signals produced this way are processed inside the MinION and sent through the USB port to your computer, where the string of bases is reassembled as a genome sequence. How long are the pieces of string? The system can read individual strings tens of thousands of bases long—far longer than most sequencing technologies. A MinION should be able to read about a billion bases before its pores run out. That’s a third the length of a human genome. All in a device the size of a matchbox.