To help infertile couples
One of the primary reasons that those who support cloning put froth in support of their cause is to help infertile couple achieve the dream of having a child that is genetically identical to them. In most cases when a couple cannot conceive naturally or are not suitable for in vitro fertilization it is because there is a problem with either the father’s sperm of the mother’s eggs. Cloning would allow either parent to produce offspring, but it would be genetically identical to only one of the parents.
Cloning is a reproductive right
There are supporters of cloning that do not necessarily believe that one should clone, but they fell that one does have the right to clone, in the same way that there is the right to other reproductive technologies, contraception and abortion.
Cloning to find cures for diseases
If a child has an incurable disease and the only way that he/she could be cured later on in life would be to have a transplant, either bone marrow or kidney that is genetically identical, then the parents could clone the child and perform the transplant. The older child would be cured and the younger child would also survive, as they can live with one kidney and the loss of some bone marrow. To support cloning for this reason would then be limited to kidney and bone marrow disorders, as any other transplant would result in the death of the clone.
To have children free of genetic disorders
If both parents were heterozygous for a deadly genetic disorder (each had a recessive allele) then there is a one in four chance that the offspring will be homozygous recessive for the trait (positive for the disorder). Neither parent has the disorder because they have one dominant allele and one recessive allele, so a clone of either one of them would produce offspring without the deadly affliction. Of course the offspring would have any other undetected genetic disorder the parent has.
To recreate a lost child or relative
If a child or family member dies then it would be possible to obtain some DNA from that individual and clone the, this could possible alleviate their grief. The Report of the President’s Council on Bioethics discusses an example of this. In an imaginary case in which a father, mother, and child were involved in vehicular accident, the father is killed instantly, and the child is critically injured and dying. If the mother took cells from the dying child and cloned the that child, it could “allow her to preserve a connection with both her dead husband and her dying child, to create new life as a partial human answer to the grievous misfortune of her child’s untimely death, and to continue the name and lineage of her deceased husband.” (The President’s Council came out very strongly against human cloning and so did not find this argument compelling)
To live through a later born twin
Some supporters of human cloning saw that because they had a particularly difficult childhood that they would like to have another chance to live the life that was meant to be theirs. Some people feel robbed of the opportunities they should have had in life and so would like the opportunity to live through a ‘later born twin’.