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Hello and welcome to Health Check from the BBC where we delve into the latest medical news from around the world.
I'm Claudia Hammond.
Now in a moment a scientific first as embryos are made from human skin cells.
We'll hear how that works and what that might mean one day in the future for people struggling with infertility.
Plus, getting to the bottom of the curious relationship between long Covid and disrupted periods.
And to help me today, I have BBC health correspondent James Gallagher.
How are you?
I'm very well, Claudia.
What do you have for us today?
I'm taking a look at why some people have been giving melatonin to their children to get them to sleep at night.
And I love this idea, could eye drops one day replace reading glasses?
Now James, you've been reporting on this extraordinary scientific first,
making early stage embryos using not an egg from a woman, but human skin cells.
So how did they do this?
What did they extract from the skin cell and where did they put it?
What they're doing is they are taking a skin cell and out of that skin cell they're taking the nucleus and that is the bit that contains a copy of the blueprint for building the whole human body.
And what you do is you take that nucleus and you put it inside an egg,
a human egg, from a donor that's had all of its genetic information removed.
but that's not enough.