Radioactivity muddles the alphabet of DNA

December 17, 2013

Curtin University researchers have shown natural radioactivity within DNA can alter chemical compounds, providing a new pathway for genetic mutation.

The research, recently published in Biochimica et Biophysica Acta-General Subjects, for the first time looked at natural radioactivity within human DNA on the atomic-scale.

While radioactivity occurs naturally in our bodies as well as in every living organism across the planet, it was never before thought to affect our DNA in such a direct way.

Using high-performance computers, the research team from Curtin and Los Alamos National Laboratory were able to show radioactivity could alter molecular structures which encode genetic information, creating new molecules that do not belong to the four-letter alphabet of DNA.

Professor Nigel Marks from Curtin's Discipline of Physics and Astronomy and Curtin's Nanochemistry Research Institute said the new molecules may well generate mutations by confusing the replication mechanisms in DNA.

"This work takes an entirely new direction on research into natural radioactivity in biology and raises important questions about genetic mutation," Professor Marks said.

"We have discovered a subtle process that could easily be overlooked by the standard cell repair mechanisms in the body, potentially creating a new pathway for mutations to occur."

Professor Marks said the work was both exciting and unexpected, emerging as a spin-off from an Australian Research Council funded project on nuclear waste.

"As part of the project between Curtin and Los Alamos we developed a suite of computational tools to examine deliberate radioactivity in crystalline solids, only to later realise that the same methods could be applied to natural radioactivity in molecules," he said.

"This direction was an unplanned outcome of our research program - just the way blue skies research should be."

The natural radioactivity in focus involved the decay of carbon atoms, Carbon-14, turning into nitrogen atoms, Nitrogen-14.

Professor Marks said this was one of the most abundant forms of radioactive decay occurring in biological systems. Over a human lifetime, around 50 billion Carbon-14 decays occur within our DNA.

"While it is still not obvious how DNA replication is affected by the presence of chemical compounds that are different to the four-letter alphabet of DNA, it is quite remarkable to consider that Carbon-14 could be a source of genetic mutation that would be impossible to avoid due to the universal presence of radiocarbon in the environment," Professor Marks said.
-end-
The research paper, Carbon-14 decay as a source of non-canonical bases in DNA, is available at http://www.sciencedirect.com/science/article/pii/S0304416513004431

Curtin University

Related DNA Articles from Brightsurf:

A new twist on DNA origami
A team* of scientists from ASU and Shanghai Jiao Tong University (SJTU) led by Hao Yan, ASU's Milton Glick Professor in the School of Molecular Sciences, and director of the ASU Biodesign Institute's Center for Molecular Design and Biomimetics, has just announced the creation of a new type of meta-DNA structures that will open up the fields of optoelectronics (including information storage and encryption) as well as synthetic biology.

Solving a DNA mystery
''A watched pot never boils,'' as the saying goes, but that was not the case for UC Santa Barbara researchers watching a ''pot'' of liquids formed from DNA.

Junk DNA might be really, really useful for biocomputing
When you don't understand how things work, it's not unusual to think of them as just plain old junk.

Designing DNA from scratch: Engineering the functions of micrometer-sized DNA droplets
Scientists at Tokyo Institute of Technology (Tokyo Tech) have constructed ''DNA droplets'' comprising designed DNA nanostructures.

Does DNA in the water tell us how many fish are there?
Researchers have developed a new non-invasive method to count individual fish by measuring the concentration of environmental DNA in the water, which could be applied for quantitative monitoring of aquatic ecosystems.

Zigzag DNA
How the cell organizes DNA into tightly packed chromosomes. Nature publication by Delft University of Technology and EMBL Heidelberg.

Scientists now know what DNA's chaperone looks like
Researchers have discovered the structure of the FACT protein -- a mysterious protein central to the functioning of DNA.

DNA is like everything else: it's not what you have, but how you use it
A new paradigm for reading out genetic information in DNA is described by Dr.

A new spin on DNA
For decades, researchers have chased ways to study biological machines.

From face to DNA: New method aims to improve match between DNA sample and face database
Predicting what someone's face looks like based on a DNA sample remains a hard nut to crack for science.

Read More: DNA News and DNA Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.