Hello from the BBC World Service and welcome to the latest edition of the

documentary podcast. Every week we bring you a range of stories from our

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In 2015, I took two gene therapies in my own body that had had effects in animal models.

As far as we know I'm the only person who has done it, I am patient zero.

That sounds very scary. Isn't that too risky? I mean no one else has done it before.

Life is risky. I can't say that the therapies are 100% safe, but I can't say you're 100% going to die without doing anything.

I'm Gabri Lattorez, with the BBC World Service and this is Liz Parish.

Two years ago she performed a very risky experiment on herself.

She took a gene therapy entirely on herself. She took a gene therapy entirely untested on humans in the hope of

curing what she says is a disease. The Disease of Aging

Curing Aging It may be pure fantasy, but some serious scientists think that

significantly delaying the aging process may indeed become a possibility.

My purpose in life is to defeat aging.

I would do whatever it takes to get there.

There's really an army of researchers that work on it and they

really attack death.

Over the next half hour we'll be hearing from some of these scientists to find out how they intend to beat aging and

asking Liz how she justifies taking such a big risk. This is forever young.

Liz is 46 and she's recently moved from Seattle in the US to London. I invited her to our office on a warm

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