“EPIGENETIC INFLUENCE :We are used to thinking of genes as being the controlling factor that determines what each of us is like physically, but genes are only a tiny part of our DNA. The other 97% was thought to be junk until recently, but we now realise that epigenetics – the processes that go on outside the genes – also have a major influence on our development. Some parts act to control “switches” that turn genes on and off, or program the production of other key compounds. For a long time it was a puzzle how around 20,000 genes (far fewer than some breeds of rice) were enough to specify exactly what we were like. The realisation now is that the other 97% of our DNA is equally important.”
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