Question

To clone an animal from an adult cell, the nucleus from an adult cell from one animal is placed into an enucleated egg of another animal.
a) Describe what happens in the process of enucleation.
b) Explain why it is necessary to enucleate the egg.
b) Will the animal look like the donor of the nucleated egg? Explain your answer.

Answer 1

a) Enucleation:
In enucleation the removal of the chromosomes is done from an egg to create an enucleated egg. The metaphase II chromosomes are removed , and sometimes they are difficult to detect them due to high lipid content so Hoechst dye (HO) staining is done and subsequent short UV exposure is given to detect the DNA for it's removal.
b) It is necessary to enucleate as the cell cell loses it's own genetic information and it's chromosomes are removed and replaced with the nucleus taken from a somatic cell of the individual or embryo to be cloned.
c) The animal will be not be identical to the nuclear donor because the somatic cell nucleus and egg comes from different individuals and the clones will have different mitochondrial genes.