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0 pointsdeepnet10y ago0 comments

Epigenetics is about gene expression, the genetic code isn't changed.

The Danish/ Swedish famine study that first proved epigenetics was real showed that starvation during puberty affected the height of granchildren by switching off genes that were still present. The third generation is unaffected precisely because it is not genetic change.

Enviroment only affects genes by reproduction, successful genes are inhereted or not - there is no change in genes during a lifetime - that would be Lamarkism and he was wrong.

Lifestyle affects methlyation markers,which are added and change gene expression for a few generations.

The underlying genes are not changed and are still inhereted, once the methlyation 'wears off' everything will be as before.

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reptation10y ago

There are a lot of assumptions in there. For instance, those methylation marks may in fact lead to changes in the DNA. Epigenetic silencing is possibly associated with gene duplication: http://link.springer.com/article/10.1007/s00239-002-2446-6

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andyjohnson010y ago

Thanks for that. When I wrote "and your environment modifies your genes" I should have written "and your environment modifies how your genes are expressed."

I'll amend my comment.

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