"Sexual reproduction typically involves two haploid cells merging to form a diploid cell. From one copy of each gene to two copies from different parents.
In vertebrates and some other organisms, this involves diploid adults producing haploid gametes, male and female. Other systems exist, including haploids being the main form.
Other systems might exist but would be pointlessly complex.
It can be done artificially. what we have now is the tiny set of genes from mitochondria used to help a woman whose own mitochondria are defective. The resultant baby will be almost identical to what she'd have got without that genetic disease.
You can also get individual genes inserted into plants and animals, sometimes from a completely different organism. Theoretically a multi-parent organism could be assembled, even a human. In practice we have far too little knowledge of how things work and it should need decades, maybe centuries. " ( Williams 1)
-some guy on quora