Identical Twins, Different DNA

Posted by Laurie Pawlik-Kienlen Feb 20, 2008

Identical twins aren't genetically identical after all, according to new research from 5 different universities and medical institutes in America and Europe.

If twins don't have the exact same DNA, that means that they're not really identical. This explains why one twin gets a disease, and the other doesn't. Doctors once believed this was due to environmental factors, but this new research shows that it could have been genetic after all.

This discovery changes how all those experiments on identical twins were analyzed. Researchers explored everything from depression to career choices in twins, and thought the results were due to the environment. Maybe they were assuming too much!

My mom is an identical twin; her sister died a couple of years ago from a horrible long-term chronic illness. My mom doesn't have the same illness -- or any indication of it. I guess it wasn't the environment that caused my aunt to get sick, perhaps it was in her DNA all along.

For a summary of the study, go to Identical Twins Not As Identical As Believed (University Of Alabama, February 20, 2008, ScienceDaily).