It's an epigenetic process. In some instances methyls get into cell nucleus and manage to work their way down a strand of DNA "blocking" expression of genes further down the line.
There's another process where something gets "de-methylated" and genes thought to be dormant get expressed.
The genes don't change at all.
52 posted on 07/18/2006 10:01:24 AM PDT by muawiyah
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