DNA’s Hidden Layer Is Real, and Physicists Are Finding More Proof

Physicists confirm the presence of a second layer if information in DNA that determines how it folds and what kind of cells it creates.

A colorful representation of DNA
A digital representation of the human genome August 15, 2001 at the American Museum of Natural History in New York City. Each color represents one the four chemical compenents of DNA. (Photo by Mario Tama/Getty Images)

Maybe you've wondered, as I have, how it could possibly be that all of the different types of cells in our bodies are made up of the same DNA chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). These chemicals pair off into A/T and C/G base pairs which then form into sequences, or “genes." So how could the finite number of possible sequences create such a wide range of things, from eyeballs to teeth, hair to heart muscle?


A lab technician handles a sample of DNA at the Genetic Institute Nantes-Atlantique (IGNA) on December 10, 2015 in Nantes, western France. The Genetic Institute Nantes-Atlantique (IGNA) is one of the first French laboratories of forensic expertise to use DNA evidence to establish the physical characteristics of a suspect and so his 'genetic sketch,' can be used as a 'support tool ' in an investigation. (GEORGES GOBET/AFP/Getty Images)

Every cell contains a sequence of some six billion base pairs that are just under 79 inches long(!), or two meters, in length. To fit into something as small as a cell, it's folded in on itself into a dense bundle—containing about 10,000 little loops—called a nucleosome. The answer to the question above—and it's something geneticists have known since the 1980s—is that what's produced by a DNA strand is determined by the way the sequence is folded. The base pairs that wind up on the outside of the nucleosome are expressed as proteins and influence the cell's characteristics, while the ones folded away into the inside aren't and don't.

The obvious question is what determines how a sequence is folded. It turns out specialized proteins in the DNA form a kind of “second layer" of information—really, mechanical cues—that determine how it will fold.

A vial containing a few droplets of water -- and one million copies of an old movie encoded onto DNA -- is displayed during a media tour at Technicolor's Sunset Boulevard studios in Hollywood, California, March 30, 2016. (ROBYN BECK/AFP/Getty Images)

Now physicists at Leiden University in the Netherlands have confirmed the presence of this second layer of instructions via computer simulations of baker's yeast and fission yeast sequences, with various mechanical cues added randomly as a second level of information. The genes in their simulations expressed differently, as expected, based on what was folded to the outside and what wound up on the inside.

Most exciting is the promise that Leiden's work could herald the beginning of simulations that would allow future scientists to manipulate folding to, say, move a person's destructive, disease-causing genes to the inside of cells where they'll do no harm. A very different way to help keep us humans healthy.

How tiny bioelectronic implants may someday replace pharmaceutical drugs

Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.

Left: The vagus nerve, the body's longest cranial nerve. Right: Vagus nerve stimulation implant by SetPoint Medical.

Credit: Adobe Stock / SetPoint Medical
Sponsored by Northwell Health
  • Bioelectronic medicine is an emerging field that focuses on manipulating the nervous system to treat diseases.
  • Clinical studies show that using electronic devices to stimulate the vagus nerve is effective at treating inflammatory diseases like rheumatoid arthritis.
  • Although it's not yet approved by the US Food and Drug Administration, vagus nerve stimulation may also prove effective at treating other diseases like cancer, diabetes and depression.
Keep reading Show less

Japan finds a huge cache of scarce rare-earth minerals

Japan looks to replace China as the primary source of critical metals

Rare-earth magnets (nikkytok/Shutterstock)
Technology & Innovation
  • Enough rare earth minerals have been found off Japan to last centuries
  • Rare earths are important materials for green technology, as well as medicine and manufacturing
  • Where would we be without all of our rare-earth magnets?
Keep reading Show less

Physicist creates AI algorithm that may prove reality is a simulation

A physicist creates an AI algorithm that predicts natural events and may prove the simulation hypothesis.

Pixellated head simulation.

Credit: Adobe stock
Surprising Science
  • Princeton physicist Hong Qin creates an AI algorithm that can predict planetary orbits.
  • The scientist partially based his work on the hypothesis which believes reality is a simulation.
  • The algorithm is being adapted to predict behavior of plasma and can be used on other natural phenomena.
Keep reading Show less
Photo by AJ Colores on Unsplash
Mind & Brain
Why do some people fight and others flee when confronting violence?
Keep reading Show less
Coronavirus

Eight women at the forefront of the world’s COVID-19 response

Beyond making up 70% of the world's health workers, women researchers have been at the cutting edge of coronavirus research.

Quantcast