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Author Topic: Do recent findings necessitate new theories of genetics?  (Read 8426 times)

Offline Martin J Sallberg

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Re: Do recent findings necessitate new theories of genetics?
« Reply #25 on: 23/05/2013 09:04:29 »

Can you give me any known examples of this kind of process in biology, where a cell somehow senses that it is malfunctioning in some general way and then "searches" for a novel substance, or genes that code for a novel substance, that it has never required in the past?

Yes. The "hypermuation" in certain immune system cells actually specifically targets the relevant genes, which is unexplainable by the standard definition of hypermutation as "stress lowering the cell's ability to repair errors". The only reason why it is not flat-out called directed mutation is because it is non-deterministic and produces diversity, as opposed to the strawman used rhetorically by neo-Darwinists when they false-dichotomistically claim that "either you believe that mutations are completely random with respect to their results or you believe that cells have an omniscient noetic ability that produces a deterministic outcome" (sounds a lot like "you are either with us or against us").

Also, a 2006 follow-up of John Cairns 1988 study "The origin of mutants" confirmed that the frequency of the necessary mutation was millions of times higher than explainable by random chance (although not billions as originally proposed by Cairns).


Is it just a process of trial and error? The success of this would seem pretty mathematically improbable in the time span of a single organism's life, and even more improbable if the organism had to rely on this process to meet many physiological or environmental challenges.

Now you are naively assuming a single try at a time. Why should a cell not be able to try multiple mutations at once? The mutation the cell tries at once may be treated as a mutation group. The mutation groups that does not solve the cell's problem may simply be expelled, while the mutation group that gets the job done may later be pruned to eliminate meaningless genes that just happened to coincide in time with the necessary mutation.


What is so wrong with natural selection and differential gene expression within the same cell? It seems so much simpler than the process you are suggesting and a lot more likely. You constantly bring up mutational load and errors, but the potential for error in what you are proposing seems a lot greater.

Natural selection is mathematically proven to be vastly insufficient in efficiency. And the versatility of general correction means that it does not simply move the problem, but actually solves it, so the "potential for error" objection does not hold up.

It's as if each cell has to reinvent the wheel all the time.
Not true. Consider horizontal gene transfer.


And since these are somatic cells, the body has no efficient way to pass on these biological solutions or innovations to the next generation.

Bollocks. Just consider exosomes, symbiotic retroviruses and micro-RNA.
« Last Edit: 23/05/2013 09:07:36 by Martin J Sallberg »
 

Offline Martin J Sallberg

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Re: Do recent findings necessitate new theories of genetics?
« Reply #26 on: 23/05/2013 09:11:58 »



You completely ignored, say, the possibility that a cell successfully solving a problem, be it through its own mutation or a borrowing, tags copies of it as useful so that other cells recognizes it.....

Furthermore, you still do not provide one scrap of evidence of any flaws in the mathematical necessity of function-sensitive self-correction....

Martin, you're asking people to debate the likelihood, or the effectiveness, of things that do not, as far as anyone knows, actually exist.

Exosomes spreading from cell to cell in the body are known to contain both DNA and proteins.


Yes, there is "function sensitive self correction" - all sorts of physiological feedback loops that maintain homeostasis - just not the kind you are proposing.

What do you believe is the principial difference, if any?
 

Offline cheryl j

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Re: Do recent findings necessitate new theories of genetics?
« Reply #27 on: 23/05/2013 22:22:08 »



Yes, there is "function sensitive self correction" - all sorts of physiological feedback loops that maintain homeostasis - just not the kind you are proposing.

What do you believe is the principial difference, if any?

The principal difference is that in physiological feed back loops, cells respond to changes in concentrations of specific molecules, increases in CO2, H+ concentration, increases or decreases in energy containing molecules, hormones, neurotransmitters. In your theory, you still need to identify what it is the cell is sensing, when it is sensing that "something is wrong."
 

Offline cheryl j

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Re: Do recent findings necessitate new theories of genetics?
« Reply #28 on: 23/05/2013 22:53:22 »

Can you give me any known examples of this kind of process in biology, where a cell somehow senses that it is malfunctioning in some general way and then "searches" for a novel substance, or genes that code for a novel substance, that it has never required in the past?

Yes. The "hypermuation" in certain immune system cells actually specifically targets the relevant genes, which is unexplainable by the standard definition of hypermutation as "stress lowering the cell's ability to repair errors". The only reason why it is not flat-out called directed mutation is because it is non-deterministic and produces diversity, as opposed to the strawman used rhetorically by neo-Darwinists when they false-dichotomistically claim that "either you believe that mutations are completely random with respect to their results or you believe that cells have an omniscient noetic ability that produces a deterministic outcome" (sounds a lot like "you are either with us or against us").





That is actually a pretty good example that would support certain aspects your theory (see link) but it does not involve cell to cell transfer of genes. And as the article points out, hyper mutability of white blood cells has a down side - like lymphoma and autoimmune diseases.

http://en.wikipedia.org/wiki/Somatic_hypermutation

Processes like these, or epigenetics, don't contradict or disprove conventional genetic processes like genetic change through recombination of genes during meiosis, sex, and natural selection. They just add to them. I still feel you are throwing the baby out with the bath water.


 

Offline Martin J Sallberg

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Re: Do recent findings necessitate new theories of genetics?
« Reply #29 on: 24/05/2013 07:26:13 »



Yes, there is "function sensitive self correction" - all sorts of physiological feedback loops that maintain homeostasis - just not the kind you are proposing.

What do you believe is the principial difference, if any?

The principal difference is that in physiological feed back loops, cells respond to changes in concentrations of specific molecules, increases in CO2, H+ concentration, increases or decreases in energy containing molecules, hormones, neurotransmitters. In your theory, you still need to identify what it is the cell is sensing, when it is sensing that "something is wrong."

Since vital functions in the cell affect everything else in the cell, the cell will inevitably "feel ill" even if it has no specific sensor for that particular error.
 

Offline Martin J Sallberg

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Re: Do recent findings necessitate new theories of genetics?
« Reply #30 on: 24/05/2013 07:43:07 »

That is actually a pretty good example that would support certain aspects your theory (see link) but it does not involve cell to cell transfer of genes.

But the principle can be combined with gene transfer between cells. If many cells need to correct the same error (as in either a genetic defect or an environmental change requiring new adaptation) the gene transfer between cells becomes very useful. As for the mechanism, I can imagine that since exosomes contain both proteins and DNA, when an exosome containing the proteins that helps the cell get the job done comes, the cell adopts the DNA content in the exosomes that happen to be within it. While that particular cell also retains many exosome DNAs that just happened to be within it, other cells will be hit by the exosomes in a different order and therefore not promote the same "freeloaders", so only the actually useful mutations are fileshared en masse. The quantity of that means that it will start leaking into other tissues including reproductive cells. Furthermore, the vast amounts of micro-RNA released when getting the production up and running floods the body, and is reverse-transcripted into DNA in reproductive cells by the vast amounts of symbiotic retroviruses that are empirically proven to be present in the reproductive organs.


And as the article points out, hyper mutability of white blood cells has a down side - like lymphoma and autoimmune diseases.

http://en.wikipedia.org/wiki/Somatic_hypermutation

Any process can have downsides when used improperly. There is no reason to assume that a more proper use of the same process should not be able to solve those problems. See thread "Body's defences not immune to brain control".


Processes like these, or epigenetics, don't contradict or disprove conventional genetic processes like genetic change through recombination of genes during meiosis, sex, and natural selection. They just add to them. I still feel you are throwing the baby out with the bath water.

I never claimed that there was no natural selection. I just shown that it was far to inefficient, and provided a more efficient form of evolution to do the bulk of the job. I agree that it would be theoretically possible (in mutation load terms) for conventional evolution to do the job alone on very simple bacteria, although I do not believe even them to be "stupid" enough to not use anything more efficient anyway, considering the general advantages of more efficient evolution.
 

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Re: Do recent findings necessitate new theories of genetics?
« Reply #30 on: 24/05/2013 07:43:07 »

 

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