Wednesday, March 07, 2007
Beyond DNA: Nurture Over Nature
This neat story came from a surprising source, my daughter's Muse Magazine (sorry article not online). In an article entitled, You are the Guardian of Your Genes science and children's writer Diana Lutz reported on recent surprising discoveries that the epigenetic markers on the DNA of identical twins will dramatically with time (epigenetic markers are small chemical groups added to DNA).
When the epigenetic markers of 3 year-old identical twins were compared, the results were nearly identical. By the time twins were 50 years old, though, four-fold increases in variations between epigenetic markers were seen. What's more, the changes were more dramatic if the twins were raised separately and had no contact up until that point.
The data are interesting, too, because animals studies have suggested that these epigenetic changes can be passed down for several generations (up to 4 - so children, grandchildren, great grandchildren, great great grandchildren). So maybe Lamarck was a little right? Remember he's the fellow who's often laughed at for his giraffes and long necks idea in evolution.
Interestingly, some old data from the early 1900's had shown that spatial maze learning ability could be passed down through inbred mice lines (good maze runners gave birth to mice who were faster, in turn, their children were even faster). No epigenetic markers will undoubtedly being investigated as a possible source of that phenomena.
These findings might remind us that what we do is very important to what we become.
Diane Arbus photo
Epigenetics: The Science of Change
Epigenetic Differences and Twins
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