Neither a sperm nor an egg has the potential to become anything, until/unless they are combined at the right time and place.
True for humans for now, but not at all true for many species. For example, a lot of silkworms are conceived just from ova, without fertilization.
Most animals that procreate through parthenogenesis are small invertebrates such as bees, wasps, ants, and aphids, which can alternate between sexual and asexual reproduction. Parthenogenesis has been observed in more than 80 vertebrate species, about half of which are fish or lizards.
from nationalgeographic.com
If they can do it, so can we. I expect it will take just a few decades to work it out.
