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The author's 1999 paper proposes a quantum mechanic to explain adaptive mutation. They assert that E. Coli mutates to develop lactase in a lactose enviroment,

by deepnet 11y ago

The author's 1999 paper proposes a quantum mechanic to explain adaptive mutation. They assert that E. Coli mutates to develop lactase in a lactose enviroment, it does this quickly and seemingly without adverse mutations - randomness fails to explain this. McFadden and Khalili propose that adaptive DNA mutation is a quantum computation. The many possible mutations are explored simultaneously and the quantum state collapses to one highly correlated to the enviroment. Their 1999 paper A quantum mechanical explanation for adaptive mutation goes in depth. http://www.researchgate.net/profile/Johnjoe_Mcfadden/publication/12899582_A_quantum_mechanical_model_of_adaptive_mutation/links/09e4150fa9e345efc4000000.pdf http://www.researchgate.net/profile/Johnjoe_Mcfadden/publica... This has led to a new scientific discipline Quantum Biology http://www.ias.surrey.ac.uk/workshops/quantumbiology/ http://www.ias.surrey.ac.uk/workshops/quantumbiology/

titzer 11y ago
Reading their abstract makes me cringe. "The principle that mutations occur randomly with respect to the direction of evolutionary change has been challenged by the phenomenon of adaptive mutations. There is currently no entirely satisfactory theory to account for how a cell can selectively mutate certain genes in response to environmental signals. However, spontaneous mutations are initiated by quantum events such as the shift of a single proton (hydrogen atom) from one site to an adjacent one. We consider here the wave function describing the quantum state of the genome as being in a coherent linear superposition of states describing both the shifted and unshifted protons. Quantum coherence will be destroyed by the process of decoherence in which the quantum state of the genome becomes correlated (entangled) with its surroundings. Using a very simple model we estimate the decoherence times for protons within DNA and demonstrate that quantum coherence may be maintained for biological time-scales. Interaction of the coherent genome wave function with environments containing utilisable substrate will induce rapid decoherence and thereby destroy the superposition of mutant and non-mutant states. We show that this accelerated rate of decoherence may significantly increase the rate of production of the mutated state." I'm no physicist but this smacks of total BS. We know that DNA codes for proteins chemically and no sort of "entangled wave function" is going to spontaneously change an A to a G, split or recombine a DNA molecule along a particular gene boundary, or cause a duplication. The fact that some cells might generate more mutations in response to environment changes doesn't demand quantum weirdness. Did the authors ever think _maybe_ there is a good old enzyme inside cells that intentionally alters the DNA at particular locations, thereby generating mutations? WTF...
- dekhn 11y ago
  Note that Jackie Barton has already shown that conjugated pi bonds formed along DNA chains can be used to transmit information; the theory of molecular orbitals is a quantum one. Also, spontaneous mutations occur, and they're caused by interactions between bases and photons; again, these can only be explained by using quantum molecular orbital theory. I'm not going to the argue the author of your quoted statement is likely to be correct.
- deepnet 11y ago
  The abstract maybe a tad general, but the paper specifically refers to the movement of a single proton : " As initially proposed by Delbruck et al. (1935) and Schrodinger (1944) and Watson and Crick (1953), spontaneous mutations are initiated by quantum jump events such as tautomeric shifts in single protons of DNA bases." You reference catalysts and there are some indications this is a quantum tunneling phenomena : Here is a talk by Professor Nigel Scrutton of the University of Manchester who has many papers on this, Quantum effects in biological catalysis https://www.youtube.com/watch?v=SnxmHlbtJDI https://www.youtube.com/watch?v=SnxmHlbtJDI ---- Here is Donald's paper criticising McFadden and al-Khalili's ideas http://people.bss.phy.cam.ac.uk/~mjd1014/qevrev.pdf http://people.bss.phy.cam.ac.uk/~mjd1014/qevrev.pdf and their rebuttal : http://arxiv.org/abs/quant-ph/0110083v1 http://arxiv.org/abs/quant-ph/0110083v1 --- The 2012 Quantum Biology Conference at the IAS has some excellent papers - which are (too briefly) summarised into the OP article. http://www.ias.surrey.ac.uk/workshops/quantumbiology/ http://www.ias.surrey.ac.uk/workshops/quantumbiology/
- kordless 11y ago
  You say it makes you 'cringe', yet you offer no substantial argument to why you are fearful of their hypothesis. Saying things like "BS" and "WTF" is a weak attempt at hacking biases, and usually attributed to dissonance. I don't accept biased arguments as truths. Quite the contrary, I see them as indicators of an unresolved argument. I'm not afraid of their hypothesis and I welcome the truth, however weird it may be.
  - wpietri 11y ago
    I didn't read that as fear of their hypothesis. I read it as irritation with the enormous amount of quantum waffle offered by loons, quacks, and frauds. Evolutionary biology has also had to deal with pseudoscientific intrusion from the get-go. This paper may be totally legit, and quantum magic may really be how biology works. But I can totally see why someone would whip out Occam's Razor and start slashing after reading that paragraph.
teraflop 11y ago
I'm very skeptical about this as an actual phenomenon, but it's been used as the premise of a fairly interesting SF novel: http://gregegan.customer.netspace.net.au/TERANESIA/TERANESIA.html http://gregegan.customer.netspace.net.au/TERANESIA/TERANESIA...

by deepnet 11y ago

titzer 11y ago

Reading their abstract makes me cringe. "The principle that mutations occur randomly with respect to the direction of evolutionary change has been challenged by the phenomenon of adaptive mutations. There is currently no entirely satisfactory theory to account for how a cell can selectively mutate certain genes in response to environmental signals. However, spontaneous mutations are initiated by quantum events such as the shift of a single proton (hydrogen atom) from one site to an adjacent one. We consider here the wave function describing the quantum state of the genome as being in a coherent linear superposition of states describing both the shifted and unshifted protons. Quantum coherence will be destroyed by the process of decoherence in which the quantum state of the genome becomes correlated (entangled) with its surroundings. Using a very simple model we estimate the decoherence times for protons within DNA and demonstrate that quantum coherence may be maintained for biological time-scales. Interaction of the coherent genome wave function with environments containing utilisable substrate will induce rapid decoherence and thereby destroy the superposition of mutant and non-mutant states. We show that this accelerated rate of decoherence may significantly increase the rate of production of the mutated state." I'm no physicist but this smacks of total BS. We know that DNA codes for proteins chemically and no sort of "entangled wave function" is going to spontaneously change an A to a G, split or recombine a DNA molecule along a particular gene boundary, or cause a duplication. The fact that some cells might generate more mutations in response to environment changes doesn't demand quantum weirdness. Did the authors ever think _maybe_ there is a good old enzyme inside cells that intentionally alters the DNA at particular locations, thereby generating mutations? WTF...

dekhn 11y ago
Note that Jackie Barton has already shown that conjugated pi bonds formed along DNA chains can be used to transmit information; the theory of molecular orbitals is a quantum one. Also, spontaneous mutations occur, and they're caused by interactions between bases and photons; again, these can only be explained by using quantum molecular orbital theory. I'm not going to the argue the author of your quoted statement is likely to be correct.
deepnet 11y ago
The abstract maybe a tad general, but the paper specifically refers to the movement of a single proton : " As initially proposed by Delbruck et al. (1935) and Schrodinger (1944) and Watson and Crick (1953), spontaneous mutations are initiated by quantum jump events such as tautomeric shifts in single protons of DNA bases." You reference catalysts and there are some indications this is a quantum tunneling phenomena : Here is a talk by Professor Nigel Scrutton of the University of Manchester who has many papers on this, Quantum effects in biological catalysis https://www.youtube.com/watch?v=SnxmHlbtJDI https://www.youtube.com/watch?v=SnxmHlbtJDI ---- Here is Donald's paper criticising McFadden and al-Khalili's ideas http://people.bss.phy.cam.ac.uk/~mjd1014/qevrev.pdf http://people.bss.phy.cam.ac.uk/~mjd1014/qevrev.pdf and their rebuttal : http://arxiv.org/abs/quant-ph/0110083v1 http://arxiv.org/abs/quant-ph/0110083v1 --- The 2012 Quantum Biology Conference at the IAS has some excellent papers - which are (too briefly) summarised into the OP article. http://www.ias.surrey.ac.uk/workshops/quantumbiology/ http://www.ias.surrey.ac.uk/workshops/quantumbiology/
kordless 11y ago
You say it makes you 'cringe', yet you offer no substantial argument to why you are fearful of their hypothesis. Saying things like "BS" and "WTF" is a weak attempt at hacking biases, and usually attributed to dissonance. I don't accept biased arguments as truths. Quite the contrary, I see them as indicators of an unresolved argument. I'm not afraid of their hypothesis and I welcome the truth, however weird it may be.
- wpietri 11y ago
  I didn't read that as fear of their hypothesis. I read it as irritation with the enormous amount of quantum waffle offered by loons, quacks, and frauds. Evolutionary biology has also had to deal with pseudoscientific intrusion from the get-go. This paper may be totally legit, and quantum magic may really be how biology works. But I can totally see why someone would whip out Occam's Razor and start slashing after reading that paragraph.

teraflop 11y ago

I'm very skeptical about this as an actual phenomenon, but it's been used as the premise of a fairly interesting SF novel: http://gregegan.customer.netspace.net.au/TERANESIA/TERANESIA.html http://gregegan.customer.netspace.net.au/TERANESIA/TERANESIA...