Suppose a child inherit chromosomes from parents and construct a new pair of chromosome pairs.
A child can receives an 'A' or 'a' from his mother and a 'B' or 'b' from his father. So, the child can inherit chromosomes by the following four cases.
- A & B
- A & b
- a & B
- a & b
Since all the chromosomes of a person are 23 pairs, the number of cases that can appear is as follows.
Theoretically, in order to have genetically identical children, you should have more than 8 million childrens.
But, 'identical twins' are genetically identical.