January 22, 2010 | 6
You can say "Watson and Crick" in one breath, but should you try squeezing in "Nirenberg"? Along with Robert W. Holley and Har Gobind Khoran, Marshall Nirenberg won the Nobel Prize in 1968 for deciphering the genetic code—a discovery that never did for Nirenberg what the double-helix did for James Watson and Francis Crick, although it probably should have.
Because maybe then, people would not misattribute the work. In 2006 Nirenberg chanced on a just published biography of a prominent molecular biologist entitled Francis Crick: Discoverer of the Genetic Code . “That’s awful!” he recounted his thoughts in a 2007 interview with Ed Regis in Scientific American. “It’s wrong—it’s really and truly wrong!”
The genetic code refers to the sequence of nucleotides (such as adenine, thymine, guanine and cytosine, or A,T,G and C) that serve as the instructions for making amino acids, the building blocks of life. It takes three nucleotides (a "codon") to make one amino acid—but which three, and for which amino acids? In 1961, Nirenberg experimented with RNA, where uracil stands in for thymine, and cracked the code for the amino acid phenylalanine: UUU became the first word in the chemical dictionary of life.
By 1966, with the aid of key contributions from Holley and Khorana, Nirenberg had identified both the compositions and base sequences of all the genetic code’s 64 trinucleotides. For this achievement, he shared the Nobel Prize in 1968; however, he somehow became the Forgotten Father of the Genetic Code.
Why? “Personality, I guess,” Nirenberg says. “I’m shy, retiring. I like to work, and I’ve never gone out of my way to try to publicize myself. Crick told me I was stupid because I never was after the limelight.” In addition, Watson and Crick’s discovery yielded a simple, visually stunning image: a gleaming molecular spiral staircase. The genetic code, in contrast, was a mazeworks of forbidding chemical names, codons and complex molecular functions—a publicist’s nightmare.
Nirenberg, who died of cancer last week in New York City, did not publicly complain about the lack of fame for his genetic work, as he found himself drawn to other avenues of research and published dozens of papers in neurobiology after cracking the code.
You can read more about him in The Forgotten Code Cracker , which appeared in the November 2007 Scientific American.
Photo of Nirenberg c. 1962 by the National Institutes of Health, Wikipedia Commons