Dan and Scott Shillum are identical twins, genetic clones produced from the accidental division of a single fertilised egg into two embryos in their mother's womb some 40 years ago.

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With only the genetic material from the person to be cloned inside the shell of the egg, the cell would be jolted with electricity to activate cell division.

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The cell is then given a jolt of electricity to activate cell division, basically tricking the cell into doing what a fertilized egg would normally do.

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