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Author Topic: How big a role does the epigenome play in evolution?  (Read 56095 times)

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #25 on: 28/03/2010 04:49:10 »
When you put all of the information together, and think logically about everything, it seems to me that hanging on to purely random mutation as the driving force behind the diversity of life is akin to insisting the Earth is 10K years old.  This is just my opinion, and maybe after we actually know more than .0001% of what epigenomic markers are capable of we will find out my opinion is wrong.  At the same time, I have yet to see anyone come up with a good reason why I should doubt the ability of life to evolve.

That's a problem.  It's a hallmark of bad science to say "I believe this because no one has proved it wrong."  Scientific models are accepted because they have evidence to support them. Models don't get accepted simply because no one can prove them wrong. 

I agree epigenetics is intriguing, and should be studied more.  There are places in evolutionary theory that need to be refined, but there don't seem to be sufficient facts yet for scientists to say that epigenetics is the model that answers those questions.  However, if a real biologist is lurking around here who knows more details about this emerging field of study, they could say more about it. 

I don't believe it because nobody has proved it wrong, I believe it because logic and mathematics dictates it has an extremely high probability of being true.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #26 on: 28/03/2010 23:15:33 »
That's a problem.  It's a hallmark of bad science to say "I believe this because no one has proved it wrong."  Scientific models are accepted because they have evidence to support them. Models don't get accepted simply because no one can prove them wrong. 

Science is forever updating, something first proven to be fact/correct since found to be partially correct or incorrect. Bad science is agreeing with something once proven to be fact when you know there is a slight chance it can be proven to be wrong.

Breast cancer was thought to be contributed to 5-10% genetic.
Now a decade later it is proven that 45% of woman with breast cancer is attributable to BRCA1 and BRCA2 mutations.


Quote from:  http://realwomenrealstories.com.au/view-stories/?story=141
This is due to the rogue gene fault BRCA1, which was discovered only a decade ago and increases a carrier’s chances of developing breast cancer anywhere up to 85%. It is like an ancient family curse.

Quote from:  http://jnci.oxfordjournals.org/cgi/content/full/91/11/943
Prevalence of BRCA1 and BRCA2 Gene Mutations in Patients With Early-Onset Breast Cancer.


My questions are:
What causes a gene to mutate in one person and be passed down the following generations?
How would this gene mutation be benefitual to our evolution?
« Last Edit: 28/03/2010 23:19:17 by echochartruse »
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #27 on: 29/03/2010 04:25:44 »
I don't believe it because nobody has proved it wrong, I believe it because logic and mathematics dictates it has an extremely high probability of being true.

I disagree with you on that.  I also think most of the science on it also disagrees with you (see below).

Science is forever updating, something first proven to be fact/correct since found to be partially correct or incorrect. Bad science is agreeing with something once proven to be fact when you know there is a slight chance it can be proven to be wrong.

Breast cancer was thought to be contributed to 5-10% genetic.
Now a decade later it is proven that 45% of woman with breast cancer is attributable to BRCA1 and BRCA2 mutations.

Did I miss something?  When was it a "proven fact" that epigenetics causes genetic mutations that are inherited by subsequent generations?  No one here has given evidence or studies supporting the idea that epigenetics leads to permanent genetic mutations.  In fact, what I've found is that scientific studies are careful to say that the epigenetic changes are not genetic mutations. 

In other words (greatly simplified):

1) New species arise as a result of genes themselves mutating.
2) There isn't evidence that epigenetics can mutate genes. 
3) Therefore, epigenetics can't explain how new species arise.

[See: http://learn.genetics.utah.edu/content/epigenetics/inheritance/, in particular

Quote
Epigenetic inheritance adds another dimension to the modern picture of evolution. The genome changes slowly, through the processes of random mutation and natural selection. It takes many generations for a genetic trait to become common in a population. The epigenome, on the other hand, can change rapidly in response to signals from the environment. And epigenetic changes can happen in many individuals at once. Through epigenetic inheritance, some of the experiences of the parents may pass to future generations. At the same time, the epigenome remains flexible as environmental conditions continue to change. Epigenetic inheritance may allow an organism to continually adjust its gene expression to fit its environment - without changing its DNA code.

(emphasis mine)]

I agree that epigenetics would be a wonderful explanation if it allowed organisms to actually mutate their own DNA, but that just doesn't seem to have any scientific support.
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #28 on: 29/03/2010 17:23:43 »
I don't believe it because nobody has proved it wrong, I believe it because logic and mathematics dictates it has an extremely high probability of being true.

I disagree with you on that.  I also think most of the science on it also disagrees with you (see below).

Science is forever updating, something first proven to be fact/correct since found to be partially correct or incorrect. Bad science is agreeing with something once proven to be fact when you know there is a slight chance it can be proven to be wrong.

Breast cancer was thought to be contributed to 5-10% genetic.
Now a decade later it is proven that 45% of woman with breast cancer is attributable to BRCA1 and BRCA2 mutations.

Did I miss something?  When was it a "proven fact" that epigenetics causes genetic mutations that are inherited by subsequent generations?  No one here has given evidence or studies supporting the idea that epigenetics leads to permanent genetic mutations.  In fact, what I've found is that scientific studies are careful to say that the epigenetic changes are not genetic mutations. 

In other words (greatly simplified):

1) New species arise as a result of genes themselves mutating.
2) There isn't evidence that epigenetics can mutate genes. 
3) Therefore, epigenetics can't explain how new species arise.

[See: http://learn.genetics.utah.edu/content/epigenetics/inheritance/, in particular

Quote
Epigenetic inheritance adds another dimension to the modern picture of evolution. The genome changes slowly, through the processes of random mutation and natural selection. It takes many generations for a genetic trait to become common in a population. The epigenome, on the other hand, can change rapidly in response to signals from the environment. And epigenetic changes can happen in many individuals at once. Through epigenetic inheritance, some of the experiences of the parents may pass to future generations. At the same time, the epigenome remains flexible as environmental conditions continue to change. Epigenetic inheritance may allow an organism to continually adjust its gene expression to fit its environment - without changing its DNA code.

(emphasis mine)]

I agree that epigenetics would be a wonderful explanation if it allowed organisms to actually mutate their own DNA, but that just doesn't seem to have any scientific support.

Sorry, but you are completely wrong.  You really need to update your knowledge on the subject.  The reason people have been clear on what "epigenetic" changes are, is to make sure people know the definition, which I already told you.  The fact that it hasn't been proven whether epigenetics can cause permanent changes to DNA, I also mentioned.  A great many scientists are taking a new look at Lamarckian evolution, because logic dictates they have no choice.  Like I said, watch "Was Darwin Wrong?" by Naked Science, and you will see what I am talking about.

You seem to be saying that since it hasn't been proven yet, we should assume it's wrong.  By that logic, we should also assume Einstein's theory of relativity is wrong, along with the standard model of physics.

How would you care to explain the explosion of life which started ~750 million years ago?

Why is it, that life spent 3.5 billion years barely evolving?

What changed, which allowed thousands of new species to emerge in just a few million years after the explosion of life started?

Seriously, basically no evolution for thousands of millions of years, and then all of a sudden we get thousands of new species..... How could anybody possibly claim that something didn't change at that point?

If you choose to hang on to "random" mutation, that is your choice.... but so far I haven't seen anybody be able to provide anything more than a very poor argument as to why I should doubt the ability of life to evolve.
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #29 on: 29/03/2010 21:11:46 »
JP, I apologize if I was too aggressive with that; I should not have flatly stated that you are wrong, that was disrespectful of me.

Would you please explain why you feel most of the science disagrees?

The scientists are making clear what the definition of "epigenetic" mutation is, and it is most definitely not mutation to the arrangement of bases with the DNA.  They have also made very clear that it is completely unknown whether epigenetic mutation can eventually become a permanent or encourage a permanent change.  The reason they need to be clear on this, is because if it eventually is proven to happen the implications are tremendous.  A scientist is not in a position to say something is proven if they can't 100% back it up.  But even if something has not been proven, we can use mathematics and look at probabilities.

Imagine you are playing a game..... In this game, you are given a coin, and you are told you that for every time the coin lands on heads you get another coin.  For every coin you have, you get another chance to "win" another.

So you start playing the game, and you build up quite a stash pretty quick.  A little while into the game, another player joins.  Player 2 is given a coin, and the same instructions.  But player 2 realizes that the rules only say the coin has to land on heads, and nothing about the events which led up to it.  So player 2 starts placing his coins on heads, every time.  Player 2 rapidly outpaces you, and pretty soon your stash looks like chump change compared to his.

This shows how incredibly beneficial any mutation which allowed epigenetic markers to influence actual genetic mutation would be.  And strangely enough, that is exactly what we see in the fossil record ~750 million years ago.

So yes JP, you are 100% correct that it hasn't been proven, and if you have any evidence against it please share, I really have no interest in continuing a line of thought which is counter to hard evidence.  But from what I have seen so far, including the links you provided, there isn't even a shred of evidence against epigenetically originating genetic mutation.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #30 on: 30/03/2010 00:23:18 »
I agree with norcalclimber.

Quote
http://itsnotmental.blogspot.com/2009/09/brain-health-nutrition-and-epigenetics.html
Environmental Epigenetics
by
Keri Cross, A.S., A.A.

As we identify more and more epigenetically unstable locations in the human genome, screening for epigenetically susceptible diseases at an early age will be made possible, along with more accurate disease diagnosis. This knowledge will allow for more precise and effective monitoring of an individual’s health. Because epigenetic profiles are potentially reversible, preventions and therapies, such as nutritional supplementation and/or pharmaceutical treatments can be developed to help counteract and even reverse negative epigenetic alterations.

Studies have shown that many disorders, such as obesity, cardiovascular disease, diabetes, hypertension, asthma and schizophrenia, have roots in early nutrition and environmental exposure during gestation. The potential for epigenetic change continues from conception until the time of death. A person’s lifetime not only affects their own epigenome, permanently modifying things like appetite control, metabolic balance, and disease susceptibility, but that of the epigenome for generations to come as well.

Quote
http://www.threeriversbirth.com/?p=307
Dr. Randy Jirtle, professor and researcher at Duke University.   All of our cells carry the same genes, but it’s the epigenomes that tell our developing cells what kinds of cells they will develop into - hair, fat, muscle, cancer, heart, etc.  Epigenetic codes pass on as cells divide, but they are not necessarily permanent.

So you may say that epigenetics controlls genes and can be passed down generations but it appears there is no evidence of genes mutating. Is it possible that humans haven't found any evidence of evolution prior 750 million yrs ago? is it possible that species have remained the same with slight alterations caused by Epigenetics? That the Elephant in India is the same species as the elephant in Africa with distinct alterations due to epigenetics. The species of humans in China being the same species as the humans in Norway with alterations to their genome via epigenetics? That the turtles ansestors are the same species with variations casued by epeigenetics? I think so.

Did epigenetics evolve? I think without epigenetics nothing would have survived or changed to suit the environment and our evolution would not have been possible. My personal thoughts are that the process of epigentics has always existed.
« Last Edit: 30/03/2010 00:46:17 by echochartruse »
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #31 on: 30/03/2010 02:17:00 »
So you start playing the game, and you build up quite a stash pretty quick.  A little while into the game, another player joins.  Player 2 is given a coin, and the same instructions.  But player 2 realizes that the rules only say the coin has to land on heads, and nothing about the events which led up to it.  So player 2 starts placing his coins on heads, every time.  Player 2 rapidly outpaces you, and pretty soon your stash looks like chump change compared to his.

This shows how incredibly beneficial any mutation which allowed epigenetic markers to influence actual genetic mutation would be.  And strangely enough, that is exactly what we see in the fossil record ~750 million years ago.

I agree with you on this.  Epigenetic markers are here probably because they give an advantage to the organisms carrying them.  What I'm disagreeing on is that I don't think there's evidence to support the claim that epigenetic markers are responsible for such a huge proportion of genetic diversity. 

Quote
The scientists are making clear what the definition of "epigenetic" mutation is, and it is most definitely not mutation to the arrangement of bases with the DNA.  They have also made very clear that it is completely unknown whether epigenetic mutation can eventually become a permanent or encourage a permanent change.  The reason they need to be clear on this, is because if it eventually is proven to happen the implications are tremendous.  A scientist is not in a position to say something is proven if they can't 100% back it up.  But even if something has not been proven, we can use mathematics and look at probabilities.

I agree that if epigenetics causes permanent change then it means a huge shift in how we think about evolution.  I'm disagreeing that it's obviously the most probable answer to the questions in evolutionary theory.  Evolution is extremely complex and deals with staggering numbers of organisms and lengths of time, so it's hard to say that this theory is overwhelmingly the most probable.  (If epigenetics can cause permanent changes to DNA it becomes far likelier and if it can't, then it becomes far less likely).
Quote
So yes JP, you are 100% correct that it hasn't been proven, and if you have any evidence against it please share, I really have no interest in continuing a line of thought which is counter to hard evidence.  But from what I have seen so far, including the links you provided, there isn't even a shred of evidence against epigenetically originating genetic mutation.
That's my other issue.  There's no evidence against epigenetics leading to permanent mutations but there's no evidence for it either.  Science doesn't work by accepting new theories based on no one disproving them yet.  You mentioned relativity and the standard model of particle physics previously as having as much support as (permanent) evolution by epigenetics (meaning acquired permanent mutations of genes).  This simply isn't true.  Both those theories in physics have made predictions which have been rigorously tested, and they have passed those tests. 

Again, I do agree that epigenetics is intriguing and needs more study.  It could provide a lot of answers in evolutionary theory, but I think it's missing that crucial point that allows the creation of permanent genetic mutations.  We can hypothesize about what would happen if permanent mutations occurred within epigenetics, but until there's evidence supporting it, it's all very hypothetical.
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #32 on: 30/03/2010 03:04:50 »
So you start playing the game, and you build up quite a stash pretty quick.  A little while into the game, another player joins.  Player 2 is given a coin, and the same instructions.  But player 2 realizes that the rules only say the coin has to land on heads, and nothing about the events which led up to it.  So player 2 starts placing his coins on heads, every time.  Player 2 rapidly outpaces you, and pretty soon your stash looks like chump change compared to his.

This shows how incredibly beneficial any mutation which allowed epigenetic markers to influence actual genetic mutation would be.  And strangely enough, that is exactly what we see in the fossil record ~750 million years ago.

I agree with you on this.  Epigenetic markers are here probably because they give an advantage to the organisms carrying them.  What I'm disagreeing on is that I don't think there's evidence to support the claim that epigenetic markers are responsible for such a huge proportion of genetic diversity. 

Quote
The scientists are making clear what the definition of "epigenetic" mutation is, and it is most definitely not mutation to the arrangement of bases with the DNA.  They have also made very clear that it is completely unknown whether epigenetic mutation can eventually become a permanent or encourage a permanent change.  The reason they need to be clear on this, is because if it eventually is proven to happen the implications are tremendous.  A scientist is not in a position to say something is proven if they can't 100% back it up.  But even if something has not been proven, we can use mathematics and look at probabilities.

I agree that if epigenetics causes permanent change then it means a huge shift in how we think about evolution.  I'm disagreeing that it's obviously the most probable answer to the questions in evolutionary theory.  Evolution is extremely complex and deals with staggering numbers of organisms and lengths of time, so it's hard to say that this theory is overwhelmingly the most probable.  (If epigenetics can cause permanent changes to DNA it becomes far likelier and if it can't, then it becomes far less likely).
Quote
So yes JP, you are 100% correct that it hasn't been proven, and if you have any evidence against it please share, I really have no interest in continuing a line of thought which is counter to hard evidence.  But from what I have seen so far, including the links you provided, there isn't even a shred of evidence against epigenetically originating genetic mutation.
That's my other issue.  There's no evidence against epigenetics leading to permanent mutations but there's no evidence for it either.  Science doesn't work by accepting new theories based on no one disproving them yet.  You mentioned relativity and the standard model of particle physics previously as having as much support as (permanent) evolution by epigenetics (meaning acquired permanent mutations of genes).  This simply isn't true.  Both those theories in physics have made predictions which have been rigorously tested, and they have passed those tests. 

Again, I do agree that epigenetics is intriguing and needs more study.  It could provide a lot of answers in evolutionary theory, but I think it's missing that crucial point that allows the creation of permanent genetic mutations.  We can hypothesize about what would happen if permanent mutations occurred within epigenetics, but until there's evidence supporting it, it's all very hypothetical.


The evidence I have most heard touted as evidence in support of epigenetics driving genetic mutation is whales.  Whales were mammals, and evolved first on land, then moved into the ocean and "lost" their legs.  Scientists are arguing that epigenetics drove that change. 
 

Offline Geezer

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Re: How big a role does the epigenome play in evolution?
« Reply #33 on: 30/03/2010 04:44:26 »

The evidence I have most heard touted as evidence in support of epigenetics driving genetic mutation is whales.  Whales were mammals, and evolved first on land, then moved into the ocean and "lost" their legs.  Scientists are arguing that epigenetics drove that change.
 

Norcalclimber, I am no expert in this field (actually, I'm not really an expert in any field  :D) but it would be helpful if you can provide a reference for your source. I'm sure you are aware that it is possible to find a lot of opinions on the web that are not exactly scientific, even although they claim to be. I'm not saying that is the situation here of course, but references would give JP an opportunity to respond to your claim.
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #34 on: 31/03/2010 19:03:40 »
Thanks, I will definitely do so.  There really hasn't been enough research in epigenetics to see proof of directed mutation from that source(at least that I have found), but there is tons of peer reviewed evidence in favor of some form of directed mutation.  But lacking knowledge of epigenetics, the conclusions were just that life is obviously incredibly dynamic and not fully understood.  I have been busy with my family for the past few days as well as the next, but I will put together a few sources and post them asap.  It seems to me that the Naked Scientists should already know a lot of this as well though, unless I'm misunderstanding the last 5 minutes of "Was Darwin Wrong?" by Naked Science. 

Anyway, it's going to be a few days at least before I can put it together, but I didn't want anybody to think I'm just spouting off with no legitimate science to support my claims at all.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #35 on: 01/04/2010 06:29:10 »
If this is not Epigentics please explain....

Quote from: http://www.abc.net.au/science/articles/2009/11/26/2754494.htm?topic=
Scientists create Chinese 'gene map'
A large genetic analysis of ethnic Chinese has revealed subtle genetic differences within the world's most populous nation.

Scientists hope the results will help them to identify certain gene variants may render some people more vulnerable to some diseases, so targeted preventive measures can be taken and therapies may one day be found.

The study appears in the American Journal of Human Genetic.

Led by Dr Liu Jianjun, head of the human genetics group at the Agency for Science, Technology and Research in Singapore, the researchers found that inhabitants in northern China were genetically distinguishable from those in the south, a finding that was consistent with historical migration patterns in China.
Variations

Consistent genetic differences, or variants, showed up in 0.3% of the genes between both groups, says Liu.

"From this genetic map, it tells us how people differ from each other, or how people are more closely linked to each other."

"We don't know what these variants are responsible for. Some may have clinical outcomes and influence disease development. That is why we are interested in genetic variation. That will help us understand when we do disease studies."

The huge sample of 8200 ethnic Chinese participants were drawn from 10 Chinese provinces and Singapore.

Interestingly, the scientists also found genetic variants between different Chinese dialect groups.

"Different dialect groups are definitely not identical ... language is a reflection of our evolution, that's why you see the differences," says Liu.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #36 on: 01/04/2010 06:43:23 »
My appology for long quoted posts but this is what we are speaking of here
Quote from: http://www.abc.net.au/science/articles/2007/12/11/2115575.htm
Humans evolving faster than thought
Will Dunham
Reuters
moving forward

How will humans evolve in the next 5000 years? (Source: iStockphoto)
Related Stories

    * First farmers wanted clothes not food
    * Human DNA surprisingly diverse
    * Tropics the hot spot for speedy evolution

humans evolving faster Human evolution has been moving at breakneck speed in the past several thousand years, far from plodding along as some scientists had thought, researchers say.

In fact, people today are genetically more different from people living 5000 years ago than those humans were different from the Neanderthals who vanished 30,000 years ago, according to US anthropologist Assistant Professor John Hawks of the University of Wisconsin.

The genetic changes have related to numerous different human characteristics, the researchers say in the journal Proceedings of the National Academy of Sciences.

Many of the recent genetic changes reflect differences in the human diet brought on by agriculture, as well as resistance to epidemic diseases that became mass killers following the growth of human civilisations, the researchers say.

For example, Africans have new genes providing resistance to malaria. In Europeans, there is a gene that makes them better able to digest milk as adults. In Asians, there is a gene that makes ear wax more dry.

The changes have been driven by the colossal growth in the human population, from a few million to 6.5 billion in the past 10,000 years, with people moving into new environments to which they needed to adapt, adds Professor Henry Harpending, a University of Utah anthropologist.

"The central finding is that human evolution is happening very fast, faster than any of us thought," Harpending says.

"Most of the acceleration is in the last 10,000 years, basically corresponding to population growth after agriculture is invented," Hawks says.
Gene mutations

The researchers looked for the appearance of favourable gene mutations over the past 80,000 years of human history by analysing voluminous DNA information on 270 people from different populations worldwide.

Data from this International HapMap Project, short for haplotype mapping, offered essentially a catalogue of genetic differences and similarities in people alive today.

Looking at such data, scientists can ascertain how recently a given genetic change appeared in the genome and then can plot the pace of such change into the distant past.

Beneficial genetic changes have appeared at a rate roughly 100 times higher in the past 5000 years than at any previous period of human evolution, the researchers determined.

They add that about 7% of human genes are undergoing rapid, relatively recent evolution.

Even with these changes, however, human DNA remains more than 99% identical, the researchers note.

Harpending says the genetic evidence shows that people worldwide have been getting less similar rather than more similar due to the relatively recent genetic changes.

Genes have evolved relatively quickly in Africa, Asia and Europe but almost all of the changes have been unique to their corner of the world.

This is the case, he says, because since humans dispersed from Africa to other parts of the world about 40,000 years ago, there has not been much flow of genes between the regions.
« Last Edit: 01/04/2010 06:46:41 by echochartruse »
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #37 on: 01/04/2010 07:00:37 »
echochartruse, I don't think we're in agreement on what the term epigenetics means.  What is the definition of epigenetics that you're working from?
 

Offline BenV

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Re: How big a role does the epigenome play in evolution?
« Reply #38 on: 01/04/2010 07:51:15 »
It seems to me that the Naked Scientists should already know a lot of this as well though, unless I'm misunderstanding the last 5 minutes of "Was Darwin Wrong?" by Naked Science.
There could be some confusion between "The Naked Scientists", the British radio show and podcast, and "Naked Science", the American tv programme.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #39 on: 01/04/2010 12:22:02 »
  In answer to JP

Quote from: http://encyclopedia.kids.net.au/page/ep/Epigenetic_inheritance
A number of experimental studies seems to indicate that epigenetic inheritance plays a part in the evolution of complex organisms. For example, Tremblay et al. (ref. 3), have shown that methylation differences between maternally and paternally inherited alleles of the mouse H19 gene are preserved. There are also numerous reports of heritable epigenetic marks in plants.
That epigenetic heredity seems to exist trangenerationally in complex organisms can be explained by allowing for minor epigenetic changes not affecting totipotency[?]. This puts some constraints on the extent to which epigenetic changes can be brought upon DNA, but it allows for EISs to play direct evolutionary roles.

My definition: In my words, (definitely not scientific ) Epigenetics is the external influences such as food, weather, location, the parants lifestyle, behaviour etc that modify/mutate/guide and effect cells which can be inherited by offspring and further generations. Genes and DNA are virtually static. From what I understand DNA in all living creatures doesn't vary much between each. We only inherit a couple of mutant genes from our parents that may or may not effect our genes/DNA, they may be passed on but lie 'dormant' until epigenetics influences them to be permanently altered/evolved.

Therfore my thoughts about the "Chinese gene map" is that they are the same species, the same race, varying in location, lifestyle etc showing 'genetic varients' between groups due to epigenetics.

Please explain if I have it wrong.




 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #40 on: 01/04/2010 12:36:31 »
Ok.  Is an epigenetic change in your definition an actual mutation of the DNA?  In other words, would two people who have epigenetic differences have different DNA?
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #41 on: 01/04/2010 12:52:06 »
Ok.  Is an epigenetic change in your definition an actual mutation of the DNA?  In other words, would two people who have epigenetic differences have different DNA?

As I see it DNA is only the carrier of information. Epigentics effects cells directly. From what I've read DNA may or may not use this information to alter genes or cells.

2 identical twins have exact same DNA, but one may not be able to reproduce.
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #42 on: 01/04/2010 13:17:51 »
So what's the answer to the question.  Do you think epigenetics changes can directly cause DNA to mutate?
 

Offline norcalclimber

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Re: How big a role does the epigenome play in evolution?
« Reply #43 on: 01/04/2010 17:39:09 »
It seems to me that the Naked Scientists should already know a lot of this as well though, unless I'm misunderstanding the last 5 minutes of "Was Darwin Wrong?" by Naked Science.
There could be some confusion between "The Naked Scientists", the British radio show and podcast, and "Naked Science", the American tv programme.

My bad, that is exactly where the confusion is from.  Lol, I thought the TV program was made by "The Naked Scientists".  Thank you for letting me know it's not the same  :)
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #44 on: 01/04/2010 19:07:32 »
So what's the answer to the question.  Do you think epigenetics changes can directly cause DNA to mutate?
Do I think?    I think nothing is impossible.
 

Offline Geezer

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Re: How big a role does the epigenome play in evolution?
« Reply #45 on: 01/04/2010 19:43:51 »
So what's the answer to the question.  Do you think epigenetics changes can directly cause DNA to mutate?
Do I think?    I think nothing is impossible.

Seemed like a simple enough question. What's all the shouting about?
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #46 on: 01/04/2010 21:50:27 »
So what's the answer to the question.  Do you think epigenetics changes can directly cause DNA to mutate?
Do I think?    I think nothing is impossible.

Seemed like a simple enough question. What's all the shouting about?

My appology not shouting, just refering to the words
 

Offline JP

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Re: How big a role does the epigenome play in evolution?
« Reply #47 on: 02/04/2010 03:22:56 »
So what's the answer to the question.  Do you think epigenetics changes can directly cause DNA to mutate?
Do I think?    I think nothing is impossible.

Seemed like a simple enough question. What's all the shouting about?

My appology not shouting, just refering to the words

It's an important point.  The two studies you linked to above that you say demonstrate epigenetics appear to be actually comparing differences (mutations) in genes.  All the accounts I've read of epigenetics state that it cannot cause mutations in genes.  Therefore the accounts you listed above are not a direct result of epigenetics according to the definition I've seen given. 

If you have sources stating that epigenetics does cause mutations in genes, then that would change things.
 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #48 on: 02/04/2010 06:08:14 »
Quote from: http://www.time.com/time/health/article/0,8599,1951968,00.html
It is through epigenetic marks that environmental factors like diet, stress and prenatal nutrition can make an imprint on genes that is passed from one generation to the next..........The drug uses epigenetic marks to dial down genes in blood precursor cells that have become overexpressed.

Read more: http://www.time.com/time/health/article/0,8599,1951968-2,00.html#ixzz0jukVCxAK
.........The great hope for ongoing epigenetic research is that with the flick of a biochemical switch, we could tell genes that play a role in many diseases — including cancer, schizophrenia, autism, Alzheimer's, diabetes and many others — to lie dormant. We could, at long last, have a trump card to play against Darwin..........."I can load Windows, if I want, on my Mac," says Joseph Ecker, a Salk Institute biologist and leading epigenetic scientist. "You're going to have the same chip in there, the same genome, but different software. And the outcome is a different cell type."
Read more: http://www.time.com/time/health/article/0,8599,1951968-2,00.html#ixzz0jukwTf7h
Read more: http://www.time.com/time/health/article/0,8599,1951968-2,00.html#ixzz0jukfD3jr


As I mentioned previously breast cancer has now been recorded in 4 generations of woman and breast cancer is epigenetic, same as alcoholism which is hereditry.

Epigenetics is the process.
The Tasmainian Devil's are fighting against cancers of the face. There is now evidence that these cancers are caused through epigenetics. Mono culture trees cause water run off to be toxic. These rare cancers are also recorded in humans in the same location.
Epigenetics regulates genetic expression.
www.preventionandhealing.com/.../Duh-Vinci-Code-for-Tasmanian-Devils-Cracking-the-Cancer-Code.pdf

Quote from: http://www.sinauer.com/detail.php?id=2993
When the molecular processes of epigenetics meet the ecological processes of phenotypic plasticity, the result is a revolutionary new field: ecological developmental biology, or “eco-devo.” This new science studies development in the “real world” of predators, pathogens, competitors, symbionts, toxic compounds, temperature changes, and nutritional differences. These environmental agents can result in changes to an individual’s phenotype, often implemented when signals from the environment elicit epigenetic changes in gene expression.

 

Offline echochartruse

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Re: How big a role does the epigenome play in evolution?
« Reply #49 on: 02/04/2010 06:13:09 »
Quote from: http://www.ncbi.nlm.nih.gov/pubmed/20332811
Heredity. 2010 Mar 24. [Epub ahead of print]
Epigenomic plasticity within populations: its evolutionary significance and potential.

Johnson LJ, Tricker PJ.

School of Biological Sciences, University of Reading, Reading, UK.

Epigenetics has progressed rapidly from an obscure quirk of heredity into a data-heavy 'omic' science. Our understanding of the molecular mechanisms of epigenomic regulation, and the extent of its importance in nature, are far from complete, but in spite of such drawbacks, population-level studies are extremely valuable: epigenomic regulation is involved in several processes central to evolutionary biology including phenotypic plasticity, evolvability and the mediation of intragenomic conflicts. The first studies of epigenomic variation within populations suggest high levels of phenotypically relevant variation, with the patterns of epigenetic regulation varying between individuals and genome regions as well as with environment. Epigenetic mechanisms appear to function primarily as genome defences, but result in the maintenance of plasticity together with a degree of buffering of developmental programmes; periodic breakdown of epigenetic buffering could potentially cause variation in rates of phenotypic evolution.Heredity advance online publication, 24 March 2010; doi:10.1038/hdy.2010.25.

PMID: 20332811 [PubMed - as supplied by publisher]

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Re: How big a role does the epigenome play in evolution?
« Reply #49 on: 02/04/2010 06:13:09 »

 

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