Mistakes happen. It's especially important when it comes to the replication of large swaths of DNA inside our cells. It is a good thing. Life would be dead in the water if it weren't for the errors in our genes.
We don't know much about the physics of the process, which is crucial to everything from disease to genetics.
It has been suggested that the chemical sleight-of-hand that swaps one base for another is triggered by quantum in nature.
The displacement of a single hydrogen that glues together the genetic bases is a significant part of the process. The process of tunneling breaks bonds between the genetic bases of guanine and cytosine over time scales that allow permanent changes.
Under confined conditions, quantum tunneling is a natural consequence of the uncertainty in a particle's characteristics.
When you zoom in on a particle, its position becomes more vague.
It is possible for objects on this scale to travel through walls as easily as a ghost moves through a haunted house.
A fundamental feature of reality on a quantum level is how particles entangle with each other in warm, noisy environments, which makes it hard for them to scale into the macro Universe.
We have assumed that for a long time.
Marco Sacchi, a chemist, says that biologists would typically expect tunneling to play a small role at low temperatures and relatively simple systems.
They discount quantum effects in DNA. We believe we have proved that the assumptions do not hold.
The chemistry behind this common form of mutation is challenged by the team's theoretical modeling.
Scientists have believed since the early days of studying the structures and chemistry of DNA that the primary cause of the variation is the transfer of hydrogens that bond bases on opposing strands.
This movement can turn the base into a tautomer, a new molecule with the same shape but a different configuration of elements.
It is thought that the hydrogens leap across the boundary between strands through a process called a double protons transfer.
The assumption that biological systems are too hot and busy for such a quantum event to occur is incorrect.
The physicists have shown that quantum effects should cause the protons to hum back and forth at a high rate, causing the bases to blur into their tautomers.
Since the time spent as a tautomer is not long, the machinery copying a strand of DNA will not recognize it.
If this process results in an unbalanced base and tautomer, it is possible that the shift can be locked into place as a mutation.
The presence of these ghostly tautomer versions of each base is great enough for this particular category to be far more common than we realize.
It will take future experiments to confirm the predictions made in the study.
It is not yet known if quantum effects play a role in other changes of base pairs or other kinds of mutation.
Biologists are starting to understand the role quantum uncertainty plays in a range of biochemical processes.
The boundaries of the quantum universe are not as solid as we think.
Nature Communications published this research.
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