Mitochondria are tiny organelles within human cells, which produce the energy used by the cell. They have their own set of genes, which is completely separate from the DNA in the cell’s nucleus. Defective mitochondrial DNA leads to various debilitating or even deadly diseases. It is technically feasible with current in vitro technology to overcome mitochondrial genetic diseases by creating a ‘three-parent baby’. The baby’s nuclear DNA comes from two parents, while the mitochondrial DNA comes from a third person. In