Fifty-five years ago a twentysomething James Watson came to the Wellcome Trust in London hoping to gather information that would help him to elucidate the structure of DNA. Last week he returned as one of the world’s most feted scientists to open the Wellcome Collection, a fabulous jumble of medical curios, original artworks and science-themed exhibitions assembled at Henry Solomon Wellcome’s grand HQ in Euston Road. Wellcome, an American who turned a fortune by selling compressed tablets to the masses, was a somewhat perverse collector, his eye roaming from the sensual (Japanese dildos) to the sadistic (torture chairs).

Professor Watson’s has been an extraordinary life, too. His thrilling account in The Double Helix of his and Francis Crick’s race against Linus Pauling on the DNA puzzle – the book that first revealed to me that science writing could be literature – was rejected initially by publishers for being too racy (Watson chased girls – just fancy!). The joyously indiscreet memoir depicts Rosalind Franklin, whose X-ray photographs were pivotal to Watson and Crick’s eventual success, as aloof, hostile and ignorant.

So it was poignant to hear Professor Watson say, in his speech, that the decoding of the human genome should make us nicer, as well as healthier. It will, he says, afford an understanding of mental illness, inspiring compassion for those whose genomes render them less able in certain respects than others. Professor Watson has had to discover such compassion within himself; he has a son with schizophrenia. It was this that led him, this month, to become the first human being whose genome is fully sequenced and publicly available (except for a gene associated with Alzheimer’s disease; Professor Watson doesn’t want to know if he will develop it).

Given this new, softer line, I asked him whether he felt that he gave Franklin a hard time. “No,” he shrugged. “She really was awkward.” He also told the audience that Franklin “was good at maths, and mathematicians are a bit strange”. Well, I suppose one can’t be compassionate and searingly honest at the same time.

— THE revelation that Professor Watson had had his genome sequenced led me to wondering whether I would do the same. I fear that the my genome, however, is not a thing of beauty; our family history is well-stocked with cases of heart disease, diabetes, high blood pressure and stroke. I don’t relish the prospect of learning which of these nasties may tuck me up for good.

Neither do I wish to know the genetic fate of my children – it seems intrusive (it’s their genome, not mine) and pointless, unless they are at risk of an easily correctable disease. Yet biologists are predicting that new mothers will be discharged from hospital not only with their babies, but with a smart card loaded with Junior’s genetic profile.

Isn’t the joy of life that we don’t know how things will turn out?

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