Posted on 06/04/2015 5:37:50 PM PDT by 2ndDivisionVet
Scientists now know that our DNA is being altered all the time by environment, lifestyle and traumatic events.
Genetic faults caused by trauma, poor lifestyle or environmental stress can be passed down to future generations, scientists at the University of Cambridge have discovered.
Previously large studies have shown that devastating events such as famine can scar future generations, making them more prone to obesity and diabetes.
However it is the first time that the biological mechanism for the effect has been seen.
Although the same genes are passed down through generations, scientists now know that our DNA is being altered all the time by environment, lifestyle and traumatic events. It is thought that these changes drive disease, premature ageing and early death.
However it was believed that these faults could not be passed on to future generations, with the slate essentially being wiped clean.
But now scientists at University of Cambridge have found that in some areas of DNA, including those linked to mental illness and obesity, some of the faults remain.
In fact, around five per cent of our genetic code carries traces of past events, meaning that trauma, poor diet or poor lifestyle choices may by leaving a devastating legacy for children and grandchildren....
(Excerpt) Read more at telegraph.co.uk ...
If true, then the Kennedys would be turning into a bunch of brain damaged alcoholic fools from birth...
Bingo!!
It appears I’ve been spending down the family inheritance.
This is called “epigenetics”: the altering of the chemistry of individual DNA base pairs without altering the sequence.
It has been known for decades that some traits develop that are not encoded genetically. For example, some reptiles do not have XX and XY chromosomes, and turn male or female depending on whether they developed in an egg close to the center of the next (where it is warm) or closer to the edge.
There are abundant examples of traits that arise from factors other than DNA sequence, which we are only recently beginning to understand.
That statement is so raciss I am not allowed any sort of comment about it.
When I first heard of epigenetics (thank you Jonathan Park) I knew I was toast.
If events can alter future DNA of our descendants, then, in the future, people will start getting pregnant orally and anally. Guys will also start having babies, and women wont need men to get pregnant.
A man who is walloped with a baseball bat, will have grandchildren with bumps on their heads. And so on, and so forth....
Only people who lead perfect lives and don’t get into trouble and don’t do kinky things, will pass on healthy DNA.
Where’s my global warming bible?
Hey, all you guys bringing up Lamarck, quit it. Your elitist knowledge is making the rest of us look dumb. Please report to the government lobotomy center for correction.
Its been clear for a long time that there are mechanisms for retaining environmentally acquired changes in the genetic code and not simply through crude and aimless natural selection.
Thanks cyn, will ping after travel.
I’ll never forget how theatrical my Genetics 101 teacher at UC Berkeley 1963 appeared when he departed from his usually dry lecture style to rail like a holy man against Lysenko. It seemed inappropriate, for a general survey course, to get that carried away by an obscure bit of heretic genetic theory. His self righteousness, seen from a 50 year perspective, says a lot about what is wrong with academia today.
Thanks cyn.
Characteristics passed between generations are not decided solely by DNA, but can be brought about by other material in cells, new research shows. Scientists studied proteins found in cells, known as histones, which are not part of the genetic code, but act as spools around which DNA is wound. Histones are known to control whether or not genes are switched on. Researchers found that naturally occurring changes to these proteins, which affect how they control genes, can be sustained from one generation to the next and so influence which traits are passed on. The finding demonstrates for the first time that DNA is not solely responsible for how characteristics are inherited. It paves the way for research into how and when this method of inheritance occurs in nature, and if it is linked to particular traits or health conditions. It may also inform research into whether changes to the histone proteins that are caused by environmental conditions -- such as stress or diet -- can influence the function of genes passed on to offspring. The research confirms a long-held expectation among scientists that genes could be controlled across generations by such changes. However, it remains to be seen how common the process is, researchers say. Scientists tested the theory by carrying out experiments in a yeast with similar gene control mechanisms to human cells. They introduced changes to a histone protein, mimicking those that occur naturally, causing it to switch off nearby genes. The effect was inherited by subsequent generations of yeast cells. The study, published in Science, was supported by the Wellcome Trust and the EC EpiGeneSys Network.
But to a certain extent, some of this COULD be explained by crude and aimless natural selection.
Suppose in some medieval European village there were two men, neither who had yet fathered children. And then there was a terrible famine. Man 1 burned through his daily calories very efficiently, and man 2 did not. Man 2 had a gene that limited insulin’s ability to be absorbed into the body’s cells while man 1 had no such problem. Because of this, man 2 has gained a little weight by not burning all his calories. His liver is also affected, storing extra sugar. His metabolism is down, and he’s often sleepy and non-energetic, even to the point that some think he’s lazy.
However, now, due to this famine, man 1’s reduced diet makes him succumb to starvation, but man 2 hangs on a little longer. The winter wheat crop finally does not freeze solid this winter, and the famine is over. Man 2 gets to pass on his genes, even this problematic insulin resistance gene, while man two, of course, being dead, does not.
Anyways, that’s not saying events occurred this way, only how natural selection could still be the driving factor.
There’s another theory called epigenetics.
Basically, it means there are on/off switches to express certain traits, and these switches can be flipped by how you live your life, and those switch states passed on to your progeny.
So can your progeny switch them back to the original setting by their life choices?
Don’t know anything about this, so I’m asking in good faith.
I have just surface knowledge of this, but I’d think they COULD change the switches.
As someone posted earlier, the iniquities are visited to the 3rd & 4th generations.
That description of changes in histones is not *quite* correct. While histones can be chemically modified to bind the DNA wrapped around them more tightly, maintaining that DNA in an inactive state, that is not the determinant of which DNA is turned off. Essentially, the “decision” to turn off certain DNA expression is made by other proteins in the cell, and influenced by signals that often come from outside the cell. In order for a cell to duplicate its DNA in preparation for replication, it has to remove the histones from the DNA in order for DNA synthesis to occur. This fact alone suggests strongly that the modification state of histones is not heritable, but is a function of various other proteins in the cell.
The DNA undergoes methylation at certain nucleotides. Those methylation patterns are really what control whether a particular stretch of DNA is inert or active. As far as I know, the DNA methylation patterns are heritable, to a degree.
Goodness, even though I looked extensively at regulation of DNA transcription during my PhD studies, I realize now that I am horribly rusty on the whole topic of histone and DNA modification.
Thanks exDemMom! And wouldn't the histones be for men, and the hertones be for the women? /rimshot
This is news?
We Irish have known this forever. Now, excuse me while I grab another Whiskey...
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