The pioneering American geneticist Craig Venter gained fame in 2001 as one of the first people to sequence the human genome.
He came to public attention again this year when his team created the first ever synthetic life form. This landmark experiment, in which a new organism was built on a synthetic genome, was described by one researcher as "a defining moment in biology".
While some - not least the religious right - have criticised Venter for playing God, his work opens the way for scientists to create life to benefit humanity, tackle disease and improve the environment.
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