UW Team Hunts Tiny Genetic Flaws Linked to Big Problems

Jul 30, 2013

Even the tiniest misprint in a person’s genetic code can cause big health problems, but they can be hard to find. Now members of a team at University of Washington say they’ve designed a better way to track down those mutations.

If you think of DNA as a twisted ladder, each rung is made of two little structures called bases, stuck together. If even one of the billions of these rungs gets copied wrong it can have serious consequences, such as which kind of tuberculosis you get.

“For example, distinguishing multi-drug resistant TB from TB that is not drug-resistant,” said Georg Seelig, an assistant professor of electrical engineering at UW.

He helped come up with a simple way to detect those genetic flaws. First you order up some synthetic DNA designed to match the strand you want to test. This turns out to be not that hard.

“You basically send an email to a DNA synthesis company, and you say hey, I’d like the sequence A-C-T-blah-blah-blah. And the next day they send you a little test tube,” Seelig said.

Then you graft in a dye that actually glows when the homemade DNA and the specimen bond. If there’s a mutation, they don’t link up right, and there’s no glow. Then you basically just mix the two compounds in saltwater.

Seelig says it’s straightforward enough that it can be used in places without a lot of money or fancy labs. It might help doctors choose how to treat diseases like drug-resistant TB, or even some cancers.

The findings are published in the journal, Nature Chemistry.