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Hardcover | $28.95 Trade | £23.95 | 200 pp. | 6 x 9 in | 14 b&w photos, 1 line drawing | February 2015 | ISBN: 9780262028479
Paperback | $17.95 Trade | £14.95 | 200 pp. | 6 x 9 in | 14 b&w photos, 1 line drawing | October 2016 | ISBN: 9780262529938
eBook | $12.95 Trade | February 2015 | ISBN: 9780262323529
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The Least Likely Man

Marshall Nirenberg and the Discovery of the Genetic Code


The genetic code is the Rosetta Stone by which we interpret the 3.3 billion letters of human DNA, the alphabet of life, and the discovery of the code has had an immeasurable impact on science and society. In 1968, Marshall Nirenberg, an unassuming government scientist working at the National Institutes of Health, shared the Nobel Prize for cracking the genetic code. He was the least likely man to make such an earth-shaking discovery, and yet he had gotten there before such members of the scientific elite as James Watson and Francis Crick. How did Nirenberg do it, and why is he so little known? In The Least Likely Man, Franklin Portugal tells the fascinating life story of a famous scientist that most of us have never heard of.

Nirenberg did not have a particularly brilliant undergraduate or graduate career. After being hired as a researcher at the NIH, he quietly explored how cells make proteins. Meanwhile, Watson, Crick, and eighteen other leading scientists had formed the “RNA Tie Club” (named after the distinctive ties they wore, each decorated with one of twenty amino acid designs), intending to claim credit for the discovery of the genetic code before they had even worked out the details. They were surprised, and displeased, when Nirenberg announced his preliminary findings of a genetic code at an international meeting in Moscow in 1961.

Drawing on Nirenberg’s “lab diaries,” Portugal offers an engaging and accessible account of Nirenberg’s experimental approach, describes counterclaims by Crick, Watson, and Sidney Brenner, and traces Nirenberg’s later switch to an entirely new, even more challenging field. Having won the Nobel for his work on the genetic code, Nirenberg moved on to the next frontier of biological research: how the brain works.

About the Author

Franklin H. Portugal served on the scientific staff of the National Institutes of Health and was a professor at the University of Maryland University College. He is currently Clinical Associate Professor of Biology and Director of the M.S. in Biotechnology Program at The Catholic University of America in Washington, D.C. His 1979 book, A Century of DNA (MIT Press), coauthored with Jack S. Cohen, remains in print today. He worked in Nirenberg’s lab from 1967 to 1970.


“...Nirenberg's brilliant contribution deserves to be more widely known. Portugal's fascinating book can only help.”—New Scientist


“Marshall Nirenberg is one of the most important scientists of the twentieth century with his key contributions to the discovery of the genetic code. Scientific discoveries are a combination of the right people at the right moments in history with the right insight, and it helps if they are also great experimentalists. Marshall Nirenberg had all of these in spades. Science, like all human endeavors, is also very political. Franklin Portugal in his The Least Likely Man has recounted the historical period that led to our first level of understanding of the genetic code with his portrayal of Marshall’s discovery, political battles, and ultimate triumph in his quest to show how the linear DNA code leads to the linear protein code. Marshall was a friend and colleague and in my view one of the great heroes of experimental science where his data triumphed all politics.”
J. Craig Venter, Ph.D., first sequencer of the human genome
The Least Likely Man engagingly recounts the inside story of how the genetic code was deciphered in the 1960s—not by Watson & Crick and their tribe of brilliant molecular biologists—but by the least likely of scientists (Marshall Nirenberg) who did the least likely of experiments (filter binding assays). Despite its backwater beginnings, Nirenberg’s table of the 64 DNA codons has achieved iconic status as the biologists’ counterpart to Mendeleev’s periodic table for chemists and Einstein’s E=mc2 for physicists—forming the first Holy Trinity for Science.”
Joseph L. Goldstein, 1985 Nobel Laureate, Physiology or Medicine
“The DNA revolution is in full swing and among the leaders in this revolution is one seldom recognized, Marshall Nirenberg. An outsider, Nirenberg made the key discovery—how the DNA code really works—yet because he was neither brash nor boastful, he rests quietly in history. This absorbing book brings to life the story of a scientist who changed the history of biology even though he was an outsider.”
Rita Colwell, former Director and first woman to head the National Science Foundation