April 19: How Genes Turn On and Off

François Jacob, a French Jewish scientist who was awarded the 1965 Nobel Prize in medicine for his research into how cells turn genes on and off, died at 92 on this date in 2013. Jacob was the grandson of France’s first Jewish military general, and quit medical school after the Nazi invasion of France to join Charles De Gaulle’s Free French Army in London. He would serve as a medic and twice be wounded in battle, once severely enough to end his hope of becoming a surgeon. Instead, he worked as a researcher at the Institut Pasteur and investigated, with Jacques Monod and André Lwoff, the existence of regulatory genes as well as structural genes, and how the former signal the latter. Jacob also researched how cancer grows and spreads. His anti-fascist conscience was again aroused when Nobelist William B. Shockley made arguments that human intelligence is racially linked. “For the group, as well as for the species,” Jacob wrote in Le Monde and the New York Times, “what gives an individual his genetic value is not the quality of his genes. It is the fact that he does not have the same collection of genes as anyone else. It is the fact that he is unique. The success of the human species is due notably to its biological diversity. Its potential lies in this diversity.”

“What intrigues me in my life is: How did I come to be what I am? How did this person develop, this I whom I rediscover each morning and to whom I must accommodate myself to the end?” —François Jacob