Researchers studying quantum tunneling within DNA implicate these effects as a possible cause of point mutations, and believe it or not, as a possible aid to the origin of life. At the same time, the researchers cite “highly efficient DNA repair mechanisms” within our our DNA replication machinery that “includes a ‘proofreading’ ability, in which mistakes are detected and corrected.” Sounds like further evidence of an intelligently designed system.
Theoretical research suggests that quantum effects could drive mutations in human DNA. This is the latest development in an emerging field called quantum biology.
The mechanism involves proton transfer through quantum tunnelling, a process that occurs in one-quadrillionth of a second. Cells have built-in proofreading systems that help prevent these mutations.
Could quantum mechanics — a field that Albert Einstein once derided as “spooky” — affect us in a highly personal way? Quite possibly. Theoretical research is beginning to suggest that quantum effects could drive mutations in human DNA. If true, this could change how we understand cancer, genetic disease, and even the origins of life.
Scientists once thought biological systems too warm, wet, and chaotic to experience weird quantum effects like proton tunneling, in which the particle’s waveform spreads out, allowing it to blip across an energy barrier that would normally block its passage. Generally, the more heat and chaos around, the smaller the quantum effect; so, for many years, scientists thought that in the human body quantum behaviors would be too small to matter.
But you can’t find what you aren’t looking for. As quantum physicists start to poke at the messy and complex world of biology, they are finding quantum mechanics at play, even within our DNA. Welcome to the world of quantum biology.
Quantum biology
For 50 years, researchers have debated whether protons switching positions between weakly bound strands of DNA could cause point mutations. The answer seemed like no. Many studies have concluded that the intermediate base-pair states created by proton switching were too unstable and short-lived to be replicated in the DNA. But a new study published in the journal Communications Physics finds that these states can be frequent and stable, and that quantum processes may drive their formation.
Instead of preventing protons from tunnelling, our biological warmth may act as a source of thermal activation, giving protons enough energy to pop over to the other side [of a G:C base-pair]. Indeed, proton transfer through quantum tunnelling is four times more likely than predicted by classical physics. Not only are these occurrences common, but they are also long-lived. Based on previous computational studies, the researchers predict that these molecular changes should be stable long enough to be replicated — causing a mutation.
Based on the team’s calculations, point mutations should appear in our DNA much more frequently than they do. The researchers attribute this difference to “highly efficient DNA repair mechanisms” that find and undo the damage. For instance, our DNA replication machinery includes a “proofreading” ability, in which mistakes are detected and corrected — sort of like a typo. Thank goodness for biological copy editors.
The ease of proton tunneling and the longevity of these intermediate states might even be relevant to studies on the origin of life, the researchers write, because the rate of early evolution is linked to the mutation rate of single-stranded RNA. Thus, though the quantum world might seem weird and distant, it might have played a role in giving us life — and also taking it away.
Big Think