In this letter to biochemist and Nobel laureate Fritz Lipmann, Crick sought to establish priority for his and Sydney Brenner's
ideas on the genetic code. He claimed to have conceived these ideas before Marshall Nirenberg described the results of his
poly-U experiments using a cell-free system (the system Crick referred to in his letter) at the International Congress of
Biochemistry, held in Moscow in August 1961. Nirenberg's experiment proved by biochemical methods that triplets of uracil
(UUU) coded for the amino acid phenylalanine.
Number of Image Pages:
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1961-11-16 (November 16, 1961)
Original Repository: Wellcome Library for the History and Understanding of Medicine. Francis Harry Compton Crick Papers
Enclosed please find a preliminary accounts of our genetical work. I expect that by now you have proved all this using Nirenberg's
system (we hear you have n people on it, where n is a large number), but we thought we'd publish it as it makes quite
an amusing story. We had the basic idea in the summer, but only got the triples after Moscow.
I have to be at Harvard during March, and should be on the East Coast in the latter part of February. Would you like me to
give a talk at the Rockefeller on this? Let me know, as I am just starting to fill in my schedule,