More than half a century ago, US scientist Dr James Watson unlocked the secrets of DNA.
Dr Watson won a Nobel prize in 1962
The discovery, for which he won a Nobel prize in 1962, is at the root of some of today's most controversial scientific and ethical issues.
But Dr Watson too is no stranger to controversy.
Within scientific circles, the 79-year-old is known as someone who loves debate and discussion.
His latest claim that black people are less intelligent than white people has prompted London's Science Museum to cancel a talk by him, saying his views went "beyond the point of acceptable debate".
In the past, he has said a woman should have the right to abort her unborn child if tests could determine it would be homosexual.
Dr Watson, right, and Dr Crick studied DNA structure at Cambridge
He has also suggested a link between skin colour and sex drive, proposing a theory that black people have higher libidos.
In a BBC interview in 2003 to mark 50 years since the discovery of DNA, he spoke about how his findings could have influenced his own life.
On the subject of discovering genetic irregularities in unborn children, Dr Watson reflected on what it could have meant for his own son who suffers from a serious mental illness.
"I think I would be a monster to want someone to suffer the way he has... so, yes, I would have aborted him," he said.
He also spoke of how he believed cancer could be conquered in the next 10 years and future children could be born resistant to HIV.
'Secret of life'
The scientist was born in Chicago and studied at the universities of Chicago, Indiana and Copenhagen.
He then moved to Cambridge University where he met Francis Crick at the Medical Research Council Unit and they started studying the structure of DNA.
In 1953 came the "Eureka moment" and together they walked into a pub in Cambridge and declared they had just discovered "the secret of life".
The two scientists had worked out the DNA molecule was shaped like a gently twisted ladder - known as a double helix.
Their findings were published in a medical journal and created a storm in scientific communities across the world.
The discovery forms the basis of some of the most controversial scientific and ethical issues today including genetic engineering, designer babies, human cloning and so-called Frankenstein foods.
From 1988 to 1992, Dr Watson directed the Human Genome Project at the American National Institutes of Health.
He was instrumental in obtaining funding for the project and in encouraging co-operation between governments and leading scientists.
Dr Watson, now director of the Cold Spring Harbor Laboratory in New York, is in Britain to promote his latest book, Avoid Boring People: Lessons from a Life in Science.