Quantum Genetics
When people think of genetic mutations, they would normally think that they're caused by radiation, carcinogens or copying errors when replicating DNA. However, recent studies show quantum tunnelling also has an effect here.
An innovative field of Quantum Biology in which we reside
Now I can imagine you, clicking on this article, flummoxed as I was in witnessing this bizarre collection of phenomena for the first time. It was tragic enough to learn about the existence of quantum biology, an emerging field established in the 1920s, but the fact that our genes—the very ones that control our thoughts, feelings, and functions of daily life—could be affected by quantum phenomena as if we were some simple electron dictated by notions of superposition, spin, and exclusion principles truly excited me, as this article will do so for you too. (hopefully).
I implore you, dear reader, to delve into this insight of quantum genetics and be inspired to follow this noble field into its future...
DNA Mutations
Section One
Traditional DNA processes rely heavily on proteins like DNA polymerase, which ensure accurate replication and repair of genetic material during cell division. However, as we know, the DNA sequence is not immune to changes, commonly known as mutations.
These mutations can occur in different ways, but most of the time, they occur due to external stimuli. Induced mutations are often triggered by free radicals, ultraviolet light, or radiation, disrupting processes like mitosis and inducing errors into the genetic code.
The discovery of DNA and its structure by Watson and Crick was a turning point in biology. However, even before this discovery, Erwin Schrödinger suggested that the highly organised nature of genetic inheritance could only be explained through quantum mechanical principles.
In his book "What is Life?" he suggested that mutations could be caused by quantum tunnelling, where protons tunnel through potential barriers at the molecular level to result in an alteration of hydrogen bonds between DNA bases and therefore a mutation to the base code.
Quantum Tunnelling
Section Two
Quantum tunnelling occurs when a particle is able to pass through a potential barrier, which it wouldn't have enough energy to classically pass through. This can happen since a particle's position can be thought of as an infinite wave through space, where higher peaks represent a higher probability of the particle being there. Potential barriers dampen this wave, but are never able to completely eliminate it, meaning the particle always has some probability of existing on the other side of the barrier.
The classical expectation is that the particle cannot get closer to the opposing base. Still, this effect reveals that the particle's wave function is not fully confined within the barrier.
A typical metaphor for explaining this phenomenon is a ball rolling up a hill. In classical physics, a ball that has been rolled down a slope in frictionless conditions can only roll back to the same point it started on an identical slope in front of it, as no additional energy is inserted into the ball. The probability that the ball passes over the hill is exactly 0, and the probability that the hill reflects it is exactly 1. The ball never makes it over the hill. The existence of the ball beyond the hill is energetically forbidden, as can be seen in the figure at the bottom of this section.
-In Quantum Physics though, the ball can indeed exceed this barrier without additional energy-
This is a truly unbelievable effect when first heard, and whilst this sounds pretty far-fetched, quantum tunnelling is real and observable, although uncommon, with it being the mechanism for processes such as alpha decay and now- mutations within our own DNA
Mechanism
Section Three
It has been found that these spontaneous mutations can arise during transcription. As the DNA double helix unwinds, protons in the nucleotide bases shift positions due to quantum tunnelling. This shift can result in a tautomerism, when a hydrogen on an amino acid moves to another, resulting in changes to hydrogen bond formation, causing alternative forms of the nucleotides. These alternate forms pair incorrectly during replication, leading to changes in the base sequence and therefore causing an error in how a gene is expressed/a protein is made. This is referred to as Watson-Crick tautomerism which can be seen in the diagram below.
(a) Typical Watson-Crick GC base pair, (b) the single proton transfer zwitterion tautomer G À C + and (c) the double proton transfer G*C* tautomer (imino-enol). Transferred hydrogen atoms are highlighted in pink.
In addition to this, researchers at the university of Surrey have specifically found that the observed lifespan of G-C tautomers could possibly be stable enough to interfere with replication mechanisms in DNA, therefore leading to a conclusion that mutations could be caused spontaneously by tunnelling.
To see their method of calculations for this, please see: Slocombe, L., Al-Khalili, J.S. and Sacchi, M. (2021). Quantum and classical effects in DNA point mutations: Watson–Crick tautomerism in AT and GC base pairs. Physical Chemistry Chemical Physics, [online] 23(7), pp.4141–4150. doi:https://doi.org/10.1039/D0CP05781A.
Prospects and conclusion
Section Four
Applications
To finish, I should probably mention why this whole topic is relevant at all, as I’m sure you are all thinking about how impractical such a topic is. However, the application of this knowledge for the future is certainly not something to blink at with possible advancements in:
•Fields such as genetics, evolutionary biology, and medicine
•Reducing Genetic diseases caused by these mutations
•Developing drugs that stabilise DNA and prevent tautomeric shifts or proton transfers responsible for mutations.
•Quantum activity in other branches such as consciousness
•Predicting where and how mutations are likely to occur in the genome.
•Engineering DNA or RNA molecules with increased resistance to quantum tunnelling-induced mutations and therefore improved Biotechnology.
I think it is quite safe to say that this is both a fascinating and potentially profitable discovery which will allow our understanding of ourselves to exponentially increase.
I hope you have enjoyed reading this short overview as much as I did researching it and be inspired to some further research into this topic and other biological process which are being discovered to incorporate quantum processes and laws such as the ORCH OR model for consciousness by Roger Penrose or photosynthesis.
