The Washington PostDemocracy Dies in Darkness

‘Supercoiled’ DNA puts the simple double helix to shame

Crazy twisted DNA, superimposed with a simulation predicting its shape. (Thana Sutthibutpong)

When most of us think of DNA, we think of that iconic double helix shape. But when you zoom out, DNA gets a lot more complicated.

"When Watson and Crick described the DNA double helix, they were looking at a tiny part of a real genome, only about one turn of the double helix," University of Leeds researcher Sarah Harris says. "This is about 12 DNA 'base pairs,' which are the building blocks of DNA that form the rungs of the helical ladder."

[Gene editing could make pig-to-human organ transplants a reality]

Harris is one of the lead authors of a study, published Monday in Nature Communications, that imaged the intricate formations of DNA and used computer simulations to examine how they wiggle and change. 

"Our study looks at DNA on a somewhat grander scale -- several hundreds of base pairs -- and even this relatively modest increase in size reveals a whole new richness in the behavior of the DNA molecule," Harris said in a statement.

The 3 billion base pairs that make up human DNA -- about three feet worth of the stuff -- has to cram into the nucleus of each and every human cell. So it's no surprise that things get pretty twisted.

Here are the researchers describing their work in, um, a very creative way:

The researchers observed a complex variety of shapes and found that they changed and moved constantly. Because drugs work by binding to the specific shape of a molecule, the researchers hope that their work will help develop better pharmaceuticals.

"We are sure that supercomputers will play an increasingly important role in drug design. We are trying to do a puzzle with millions of pieces, and they all keep changing shape," Harris said.

Read More:

Scientists are using DNA origami to 3-D print structures just nanometers across

Gene editing could make pig-to-human organ transplants a reality

Nobel Prize in chemistry shared by American, Swedish and Turkish scientists for DNA repair

Scientists find the single letter in corn’s DNA that spurred its evolution

This blood test can tell you every virus you’ve ever had