n.
born April 10, 1927, New York, N.Y., U.S.
U.S. biochemist.
He received his Ph.D. from the University of Michigan. He demonstrated that each possible triplet (codon) of the four different kinds of nitrogen-containing bases found in DNA and (in some viruses) in RNA (with three exceptions) ultimately causes the incorporation of a specific amino acid into a cell protein. His research earned him a Nobel Prize in 1968, which he shared with Robert William Holley and Har Gobind Khorana , whose work, like Nirenberg's, helped show how genetic instructions in the cell nucleus control the composition of proteins.