A miniature DNA sequencer began 27 years ago with a quick sketch in a car. Laurel Hamers spells out the tale. Illustrated by Jay Rasgorshek.

Making the MinION

By Laurel Hamers

David Deamer was driving through Oregon when he swerved his car to the side of the highway. He dug out a steno pad and a red pen—“the only pen I had”—and hastily recorded the thought that had come to him moments before. What if, he wondered, you could detect the genetic information encoded in a strand of DNA by threading it through a microscopic hole in a cell membrane? By measuring tiny changes in electrical current as the strand passed through, one might be able to read the blueprint for life it contained. He dated the diagram June 25, 1989.

Deamer, now a research professor in biomolecular engineering at UC Santa Cruz, still has that notebook. His doodles sparked a quarter-century of research on the membrane holes known as nanopores. The intensive work—and $200 million in investments—paid off in 2014, when a British company called Oxford Nanopore released a pocket-sized device that uses the technology Deamer envisioned. The “MinION” translates DNA’s molecular message into one scientists can understand.

Deamer began investigating his idea as teams were racing to sequence, or read, the entire human genome for the first time. In 2001, researchers with the Human Genome Project unveiled our instruction manual: a complete sequence of about three billion DNA subunits, called bases, encoding the roughly 20,000 genes that shape our identities. (A team at UCSC published the first such sequence online.) But most mainstream DNA sequencers remained hulking machines, costing upwards of $100,000 and weighing nearly as much as a Mini Cooper. In contrast, the MinION sells for less than $1,000 and is smaller than an iPhone.

Eminent scientists told Deamer and his colleagues their vision would never work, and lawsuits almost derailed the project. But today, the MinION is transforming DNA sequencing by taking the technology into the field, where it helps scientists track diseases and identify species within hours. It calls to mind the morphing of computers 30 years ago from room-sized behemoths into desktop devices that anyone could own. Deamer’s chief collaborator, UCSC’s Mark Akeson, is succinct about what the MinION represents: “A democratization of sequencing.”

Photo: Laurel Hamers
UC Santa Cruz graduate student Miten Jain holds a MinION—with a guitar-playing Minion action figure looking on.









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