For someone who cracked "the secret of life" when he unravelled the double helix structure of DNA, James Watson does not seem to want much in the way of genetic improvement.
Speaking at the climax of the Newcastle Science Festival at the Centre for Life, he proved his sharp mind was as alert as ever.
Watson gives his autograph to a young scientist
As well as his momentous discovery, he is also closely involved with the project to sequence the human genome, the full set of biochemical instructions needed for our bodies to build and maintain themselves.
During a discussion about genetic alterations to human beings, Watson was asked if there were any alterations he would make to himself.
He said: "If there was anything I could change from a personal point of view it would be to get rid of my earlobes - they are superfluous and ugly."
Joking aside, Watson remains an "optimist" about the possibilities of his and Francis Crick's defining discovery at Cambridge University 50 years ago.
And Watson remains hopeful their discovery means the genetic causes behind illnesses such as cancer and schizophrenia can be combated.
He said: "We are beginning to understand the causes of disease relating to our genes not working, and we should rightly be looking to solve some of those diseases.
"I am optimistic that we might be able to stop most cancers."
The hall was packed with people of all ages, from youngsters reading science, to pensioners who probably remember Crick and Watson's breakthrough in 1953.
'Help of others'
On 25 April, 1953, the science journal Nature published a paper by him and Francis Crick describing their model of the structure of DNA.
The pair went on to receive a Nobel Prize for their work, together with Maurice Wilkins of King's College London, who carried out key experiments on DNA.
Watson said: "It doesn't seem that long ago when I look back now. I can still remember the feeling of euphoria when we realised that information was presented twice.
"We realised you could copy this information if you separated the two strands. Francis said to me: 'We have discovered the secret of life' - and we had."
James Watson (right) listens as Francis Crick recalls their find
However, he modestly claimed had they not made the discovery then others would have at a later date.
Francis Crick told the audience, speaking via video-link as he was too ill to attend the event, that the pair then went to the pub to celebrate.
Crick continued: "The discovery of the double helix was an important breakthrough, but we couldn't have done it without the help of a lot of others."
A small picket of protesters was outside the event, leafleting visitors about the dangers of "Nazi-style eugenics".
However, Watson said: "Deaf couples can choose to have deaf children. I would say that does not seem sensible to me, but it is their right.
"We are not going to manipulate things so that all people are the same, or look like the movie stars of the day.
"However, if you can have all human beings immune to cancer, is that such a bad thing? If you can prevent children being ill, is that so bad?"