Genetic progress forward

Geneticist view

A clone is a true twin, although its birth will occur quite a long time after its model ...

A true twin is the result of the division/splitting of one egg in two identical ones : two individuals with an equal gene pool will then be produced.
First cloning experiments consisted in dividing the few cells of a young embryo in two equal parts which implied true twins natural recreation.

Here is the somatic cloning novelty :
  1. Use of an adult cells rather than an embryo's ones.
  2. Use of an oocyte as a receiver in view of the subsequent development.
  3. Staggered birth between true twins.
However, there is a slight genetic difference between both donor and its clone : 1 or 2 % of the DNA will come from to the receiver's oocyte since mitochondrion DNA is conveyed by maternal cells only.