Nuclear Transfer

Taking the nucleus out of a somatic cell and transferring it to a "de-nucleated" egg cell

Like micro-injection, nuclear transfer is a standard method for producing genetically modified animals. First, DNA encoding new genes is added to a somatic cell. Then, the modified somatic cell's nucleus is transferred to an unfertilised egg cell. The egg cell's own nucleus has to be removed beforehand. The result is a clone of the original somatic cell with the desired genetic modification. The transformed egg cell is then grown into an early-stage embryo, which is transferred to the womb of a surrogate mother. 

Nuclear transfer was used to clone the sheep "Dolly". In the case of Dolly, however, the somatic cell's nucleus was not genetically modified.