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Hello, when he was mortally ill with cancer, the British geneticist JBS Holden came up with the following

gallant lines.

Cancer is a funny thing. I wish I had the voice of Homer to sing of rectal carcinoma, which

kills a lot more chaps in fact, than were bumped off when Troy was sacked.

Professor Holden Neubet, Holden knew better than most that many cancers

and many other diseases are caused by genetic mutation. Indeed, to understand mutation

fully may explain the ravages of illness and even unlock the secrets of aging.

But mutation, so often a destroyer of life, is also its creator.

Without it, the variety of living things on Earth simply wouldn't exist.

It is, in the Darwinian view of life, the raw material of evolution.

With me to discuss mutation in genetics and evolution, a Steve Jones, Professor of Genetics in the Galton Laboratory University

College London, Adrian Wolfson, a molecular biologist who teaches medicine at Cambridge,

Weldon Professor of Biometry at the University College London.

Steve Jones, can you explain what mutation is?

Mutation sounds simple in some ways it is.

It's simple errors in copying

which then material mistakes and evolution is a series of

successful mistakes picks up the mutations that

are better at copying themselves in the wild.

Historically, it was first of all seen as something rare and exceptional that almost never

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