All identical twins may share a common set of chemical markers on their DNA
Testing for the marks could reveal if someone was conceived as an identical twin
![twin girls stand side by side](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2021/09/092721_JL_twins_feat.jpg?fit=1030%2C580&ssl=1)
Pairs of identical twins share the same set of genes. New research reveals that identical twins everywhere also share a set of chemical tags along their DNA that denotes they developed in the womb as a twin.
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