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Author Topic: How big a role does the epigenome play in evolution?  (Read 56021 times)

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #175 on: 25/04/2010 00:08:27 »

If the epigenome tells a cell what type of cell to be, isn't it plausible that cancer may actually be epigenetic?

sites in support:


http://www.news-medical.net/news/2004/12/20/6892.aspx
Rett Syndrome, the first identified epigenetic disease - linked to specific defects in the three-dimensional folding of chromatin. 20. December 2004

http://www.nature.com/nature/journal/v429/n6990/full/nature02625.html

http://cancerres.aacrjournals.org/cgi/reprint/62/22/6784.pdf

http://www.cmaj.ca/cgi/content/full/174/3/341


Quote from: http://www3.interscience.wiley.com/journal/88512946/abstract?CRETRY=1&SRETRY=0
Cancer is an epigenetic disease at the same level that it can be considered a genetic disease. In fact, epigenetic changes, particularly DNA methylation, are susceptible to change and are excellent candidates to explain how certain environmental factors may increase the risk of cancer. The delicate organization of methylation and chromatin states that regulates the normal cellular homeostasis of gene expression patterns becomes unrecognizable in the cancer cell. The genome of the transformed cell undergoes simultaneously a global genomic hypomethylation and a dense hypermethylation of the CpG islands associated with gene regulatory regions. These dramatic changes may lead to chromosomal instability, activation of endogenous parasitic sequences, loss of imprinting, illegitimate expression, aneuploidy, and mutations, and may contribute to the transcriptional silencing of tumour suppressor genes.

I seem to be flogging the devils... but I believe this tumor associated with the run off from the mono culture of genetically modif
ied native trees (modified so they are fire retardant, I believe)has silenced the devil's tumor suppressor genes. the devils are unable to identify the cancer gene, as its DNA is similar to the devils, (which has been refered to at another posted link).

The fact that no chemical could be associated with this cancer has delayed the progress to over come it. The genetically modified mono culture trees natural oils running into the water system is proving to be the culprit.
Quote from: http://www.abc.net.au/austory/content/2007/s2820402.htm
DR MARCUS SCAMMELL, MARINE ECOLOGIST: The Tasmanian Government’s conclusion was that it was naturally occurring toxins and therefore it’s okay....DR MARCUS SCAMMELL, MARINE ECOLOGIST: Everything that we knew could cause toxicity we had eliminated.....DR CHRIS HICKEY, ECO-TOXICOLOGIST, NATIONAL INSTITUTE OF WATER AND ATMOSPHERIC RESEARCH, NZ: It told us we were looking for something different, something unusual. I think they really may have stumbled on something quite new.


Quote from: http://www.abc.net.au/austory/content/2007/s2827187.htm
Because what disease in wildlife populations tends to be is a harbinger of instability, of a breakdown in normal cycles of a population reaching a stable balance with other animals interacting with their ecology. And perturbations, whether they are human induced, or the fact that we’ve actually through our agency allowed for the introduction of new pathogens. This is the brave new world that we face in the 21st century.
    please read this link.

Quote from: http://www.454.com/about-454/news/index.asp?display=detail&id=139
    In order to identify the tissue of origin of the tumors, the team used the Genome Sequencer FLX System to sequence both diseased and healthy transcriptomes-- the complete set of genes that are “turned on” in a specific cell. The researchers then compared gene expression results between the two tissues and found that the tumors’ genetic signature best matched that of Schwann cells found in the peripheral nerve. The underlying mechanism for how these nervous system cells spawned cancer cells is still unknown.....Murchison et al. The Tasmanian devil transcriptome reveals Schwann cell origins of a clonally transmissible cancer. (2009).


Quote from: http://www.abc.net.au/austory/content/2007/s2827178.htm
DR MARCUS SCAMMELL, MARINE ECOLOGIS............St Marys is surrounded by natural forest. And we’ve found no evidence of toxicity in the St Marys catchment. However in the St Helens catchment directly below this monoculture of plantation trees, we had permanently present toxin.


DR ALISON BLEANEY, GP & LOCAL COUNCILLOR (at South Georges River): This is the head waters of the South George which feeds into the George River, and here we are surrounded by plantations. This used to be natural bush and farming land and now we are completely surrounded by plantations here - the Eucalyptus Niters. This is the source of our drinking water for St Helens, let alone all the animals that drink from it, and this is one of the areas where we’ve discovered that the water in fact is toxic. This should be the most pristine water. This is the very head waters of the South George. Where is this toxin coming from?

(Excerpt of Dr Alison driving to visit patient)
DR ALISON BLEANEY, GP & LOCAL COUNCILLOR: I’m off to go and see a patient who’s got a very... a very rare cancer - Waldenstrom’s Anaemia. She’s one of only approximately 18 in Australia, and we just happen to have two in St Helens. And in the last perhaps six years or so we’ve actually seen quite few people with really quite rare autoimmune diseases of their brain for instance. We’ve had a case of Wegener’s Granulomatosis; it’s actually quite a rare disease.
So now looking back on this over the last ten years, I realize that I see many things now that as a GP... that many GPs would never see one of these cases in their working lifetime. Clearly in a population of less than 3,000 to have these rare diseases - to have this chronic ill health - there must be something on the go to explain this.

therfore I believe the Tassie devil's rare cancer is epigenetic

 

Offline grizelda

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Re: How big a role does the epigenome play in evolution?
« Reply #176 on: 26/04/2010 21:48:34 »
Possibly the trees have introduced a new toxin into the environment which is causing cancer in the human population and wildlife. The lineages of the populations that are susceptible to this will die off and those lineages whose genetic structure can cope will survive. The Tasmanian Devils have no immunity because some event in the past reduced their numbers to a few mating pair and all devils extant are descended from them. This lineage lacks the genetic protection or it has been damaged.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #177 on: 27/04/2010 00:12:29 »
Possibly the trees have introduced a new toxin into the environment which is causing cancer in the human population and wildlife. The lineages of the populations that are susceptible to this will die off and those lineages whose genetic structure can cope will survive. The Tasmanian Devils have no immunity because some event in the past reduced their numbers to a few mating pair and all devils extant are descended from them. This lineage lacks the genetic protection or it has been damaged.

Yes the trees are apparently a native species and the run off is natural oils but in extremely large doses due to monoculture style of planting. It has been said the trees are genetically modified with a fire retardant. whether that has anything to contribute to the problem, needs to be established.

Because the toxins occur naturally in the trees nothing has been done about it.

This disease kills quickly and the devils seem to be responding by breeding at a much earlier age.
Yes their genetic pool was very limited as you mentioned.
But 10 years after the disease we are finding the gene variation in the devils are more varied.
Hoping to breed them with the captive devils and release them into the wild with the plan they will better breed and pass on immunity.

the cancer may have caused the devils to evolve or adapt or help them adapt over time.
« Last Edit: 27/04/2010 00:15:10 by echochartruse »
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #178 on: 17/05/2010 20:35:10 »
One aspect of the epigenome which I find extremely interesting is that both advantageous and deleterious traits seem to be passed on by the actions or experiences of an organism; i.e. In the Time article I cited a bit back, the descendants of those who had experienced times of extreme abundance in food were actually less fit than descendants of those who had to struggle.

I guess what I am curious about with this is:  In the past(and present) an omnipotent creator watching over us constantly has been used to encourage morality and balance in life; I personally do not believe in said creator, but could the epigenome replace that?  If all our actions and choices will be passed on to future generations, am I potentially dooming my children and grandchildren by my actions?
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #179 on: 18/05/2010 01:34:15 »
One aspect of the epigenome which I find extremely interesting is that both advantageous and deleterious traits seem to be passed on by the actions or experiences of an organism; i.e. In the Time article I cited a bit back, the descendants of those who had experienced times of extreme abundance in food were actually less fit than descendants of those who had to struggle.

I guess what I am curious about with this is:  In the past(and present) an omnipotent creator watching over us constantly has been used to encourage morality and balance in life; I personally do not believe in said creator, but could the epigenome replace that?  If all our actions and choices will be passed on to future generations, am I potentially dooming my children and grandchildren by my actions?

The amazing thing about our genome influenced by our actions today which influence following generations is that there is 'choice' definitely not 'random'. The fight for survival is calculated.

For example, even though the devils did not have a choice in getting the cancer, there genome has chosen to allow them to mature earlier so they may breed earlier to a benefit of their survival in hope that generations will cope/acquire immunity to fight the cancer.

It doesn't entirely depend on you passing on the diseased gene but also what the next generation does with it. As someone said earlier here, just because a family has long generation of say breast cancer/ alcoholism, diabetes, whatever doesn't mean every person there after gets the genetic disease
There is choice which some see as Random.

Maybe the 'creator' is not a man but a protein or something entirely new/undiscovered within the proteins that control and process changes in our genome.

Tibetan highlanders began to genetically adapt to prevent polycythemia, should their children live at lower altitude then their genetic adaptations would alter to suit the conditions over just a few generations.

Whatever the source is for the process's initiation for our genome to cope, it is not random but logical and calculative.

It will be very exciting when we find what actually determines which genes are expressed.
http://www.sciencedaily.com/releases/2009/10/091009104646.htm
http://www.sciencedaily.com/releases/2007/12/071214094106.htm

Definitely intelligent process.
« Last Edit: 18/05/2010 01:42:26 by echochartruse »
 

Offline BenV

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Re: How big a role does the epigenome play in evolution?
« Reply #180 on: 18/05/2010 08:03:10 »
Once more, echo, you are seeing intent and intelligence where there is none.

Things do seem to change in a directed way, but this does not mean there is intent there. You and Norcalclimber are making very different points.
 

Offline imatfaal

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Re: How big a role does the epigenome play in evolution?
« Reply #181 on: 18/05/2010 15:28:39 »

http://www.sciencedaily.com/releases/2009/10/091009104646.htm

http://www.sciencedaily.com/releases/2007/12/071214094106.htm

Definitely intelligent process.


The article behind the news story in the first link deals with various proteins and cellular factors that interract with DNA to determine transcription and elongation.  it deals with the actual three dimensional structure of the RNA polymerase II - transciption factor complex and how this binds to certain codes within the DNA.  it is neither evidence nor claims to be of an intelligence behind transcription.

The second article deals with phosphorylation of rna-polmerase II (specifically the repeat of 7 peptides in the tail) and how this affects trasncription - and whilst phosphorylation is a potential path of epigenetics the article does not deal with this explicitly.  it does not touch on any intelligence or guidance behing transcription.


These articles in no way promote your argument.
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #182 on: 18/05/2010 19:47:14 »

The amazing thing about our genome influenced by our actions today which influence following generations is that there is 'choice' definitely not 'random'. The fight for survival is calculated.

I agree that there are some changes in the epigenome which could be called "chosen" by us, because we all choose how we will live our life.  But I do not agree that everything in survival or evolution is "chosen".  In fact I feel it is pretty well proven that everything is definitely not chosen because deleterious mutations do in fact happen.

It doesn't entirely depend on you passing on the diseased gene but also what the next generation does with it. As someone said earlier here, just because a family has long generation of say breast cancer/ alcoholism, diabetes, whatever doesn't mean every person there after gets the genetic disease
There is choice which some see as Random.

I have to completely disagree, I don't think anybody chooses to get breast cancer.  You are correct that the next generation has influence as well, but I do think it is random whether you get breast cancer or not.



Maybe the 'creator' is not a man but a protein or something entirely new/undiscovered within the proteins that control and process changes in our genome.

I see no evidence anywhere of any "creator" of any type or sort whatsoever.  When I started this thread I was warned that my use of "intelligent design" could be confusing, and I see now they were completely correct.

Let me be clear;  When I referred to the possibility of intelligent design, I was referring to the possibility that experiences can be passed down to offspring via the epigenome and that maybe those changes which were specific responses to environmental shifts allow life to evolve at a much faster rate than by purely random mutations.  I feel the fossil record implies this probably developed around 750 million years ago, but while there wasn't much evolution prior to that, it would be incorrect to say there was none.  I believe that most likely all of the mutations which drove evolution prior to ~750 million years ago were essentially random.

Tibetan highlanders began to genetically adapt to prevent polycythemia, should their children live at lower altitude then their genetic adaptations would alter to suit the conditions over just a few generations.

Whatever the source is for the process's initiation for our genome to cope, it is not random but logical and calculative.

I only partly agree with this.  Yes, I do think there is a non-random element to evolution.  Yes, due to mathematics I believe this non-random element is responsible for the vast majority of the diversity of life we can observe. 

I do not believe that nothing is random though.  In fact, I think that by looking at our Universe we can see that "random" is extremely important.

It will be very exciting when we find what actually determines which genes are expressed.
http://www.sciencedaily.com/releases/2009/10/091009104646.htm
http://www.sciencedaily.com/releases/2007/12/071214094106.htm

Definitely intelligent process.

Yes, it will be very exciting to find out more about the epigenome.

No, the process is not intelligent, it is life itself, the specific individual be it fruit fly or human that I find intelligent.  The process cares for nothing, it is nothing but a process. 

But life on the other hand....absolutely brilliant!!
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #183 on: 19/05/2010 02:01:05 »
In order to avoid confusion with creationism, which is the origin of the "intelligent design" phrase, I am changing the title question of this thread.
 

Offline echochartruse

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How big a role does the epigenome play in evolution?
« Reply #184 on: 21/05/2010 19:53:13 »
Evolution through natural selection.
What comes first the change in the genome or change in the environment?
"Random mutation that natural selection can act upon"?
Or could it be due to the environment that one life form’s genome changes which effects another life form? all due to epigenetics.
Say for example a disease such as cancer caused by contaminated environment has found its way into a host species and has developed strategies to regulate cell expression to allow itself to be undetected allowing itself to be transmitted throughout a specific species of animal while this disease constantly evolves, assisted by the very low genetic diversity of that animal species. Then almost instantaneous adaptation/selection" for younger animals across the species to reproduce happens. Is this truly 'random mutation' or esential mutation for that species to exist?
Therefore over time if nature took its course the population would probably bounce back. Genetic drift is said to be random. In this case the random factor would be which individual/individuls were capable of passing on the immunity. If none did then the species is lost forever. Immunity is esential for this species to exist
Natural Selection, a specific trait increases in the population because it is better adapted to the changed environment.
With Genetic Drift, a specific trait increases in the population simply because a random event caused there to be slightly more of one and less of another leading to the more populous being more likely to breed.

Epigenics is the cause, natural selection is the effect.

Is the ability for the species genes to adapt allowing them to breed earlier random or essential?
In this case the events are random not the mutation which is essential for life itself.

I recently saw a documentary stating that without Jupiter earth would not exist. Therfore I believe epigenetics is most important for evolution and most probably the major cause for evolution/adaptaion, not because a random gene mutation happened that nature had to act upon  to compensate to allow life to exist.
 

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How big a role does the epigenome play in evolution?
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