English: Identical twins Dansk: Enæggede tvill...

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We have always considered identical twins to be identical. In fact their DNA is the same but we now know there is another level to our genetics called epigenetics (above genetics). In fact identical twins have different epigenetics even at birth. As they age their epigenetics differs more and more causing them to sometimes look different, get different illnesses and think differently. We must rethink and write new textbooks on what identical means.