He was trained as a physicist, and after the war he wanted to do biophysics, and he picked DNA because DNA had been determined at the Rockefeller Institute to possibly be the genetic molecules on the chromosomes.
On je bio školovani fizičar, a nakon rata htio se baviti biofizikom i odabrao je DNK jer je DNK bila utvrđena na Institutu Rockefeller kao moguća molekula genetičkog materijala u kromosomima.