Skin cells might be used instead of eggs to make embryos
theguardian.comThis makes sense in that it is less invasive and skin cells are more plentiful but the current invasive methods at least ensure that there is consent.
If you could surreptitiously get enough of someone's skin cells you could create an embryo with no consent. It's a given that this won't be within the ability of Mr and Mrs J Public but it's still something that creates concern.
I'd not worry too much for now. If you remove all the statements about how great this would be, it's vaporware. From the article:
> The potential to use skin cells instead of eggs remains highly speculative for now. But if researchers can overcome the remaining hurdles, of which there are many, they could in theory create embryos [...]
The experiment they describe is misleading. They took an egg of a female mouse. Read carefully, they took initially an egg not a skin cell. Then they make it look like a skin cell using some hormones. Then they took the egg that looks like a skin cell and fertilized it.
The takeaway is that it's possible to make an egg look like an skin cell and fertilize it later. Perhaps this is useful to store them, or make many copies, or something.
But to use a real skin cell directly, you have more problems, in particular you must get ride of half the chromosomes ...
I can't find a good link now, but one important property if the eggs and the sperm is that they come from a cell line that is selected in the early embryo. This group of cell try to divide as few times as possible. Each cell division may produce a mutation, and mutations are usually bad, so you want as few mutations as possible for your kids.
But skin cells don't have this problem, so they divide as much as necessary. (Actually, the skin cells use some schemes to reduce the number of divisions, because and unlucky mutation may create a cancer, so you want to skip them too. But it's more easy to get a mutation that breaks some part of the early embryo development of your child than a mutation that creates an uncontrollable cancer.)