Sitting in his cluttered office at the City of Hope's Beckman Research Institute in Duarte, Susumu Ohno puffed on his pipe and contemplated the origins of life as a soothing piano piece wafted from a tape player, mixing with the aromatic smoke from his tobacco.
Drifting out his office door, the melody possessed a vaguely familiar quality, reminiscent of Tchaikovsky. But as Ohno explained to a visitor, the composition was the product of a entirely different kind of culture.
"This is a slime mold," Ohno said.
Indeed, everything from slime mold to protozoans to the lenses of chicken eyes is literally music to the Ohno's ears. In trying to determine how the first genes were formed, the scientist hit upon the idea of transcribing the chemical formulas for various genes into musical scores.
The resulting pieces, which Ohno has had recorded by a pianist and violinist, resemble a wide variety of classical music styles, from baroque to 20th-Century: the more complex the genetic structure, the more contemporary the music sounds.
"This is the very primitive gene of a protozoan, so it's a little like Bach; this is a slime mold, so it's a little more complex, more like Tchaikovsky or around that time," Ohno said, pausing to pop a cassette labeled "chicken lens" into the tape player on his desk. "This is more like Claude Debussy, don't you think?"
Ohno, 59, began turning genes into music about two years ago. He said his novel brand of research is merely a more pleasant way for him to study the origin of life, the question he has probed ever since he arrived at the City of Hope in 1953 after receiving his Ph.D. from the University of Hokkaido in Japan.
About the time he arrived, scientists at the University of Chicago performed a famous experiment to demonstrate how life may have begun on Earth. Electrical charges were sent through a mixture of water, ammonia and methane that simulated the recipe of the "primordial soup" that made up the atmosphere of the newborn planet.
Within weeks, the process resulted in the formation of basic materials such as nucleic acids, the building blocks from which all life is constructed. But although these substances were the components of life, they were not life itself.
Ohno then set upon the task of discovering how nucleic acids arranged themselves into the complex chemical patterns that permit living organisms to reproduce and evolve.
Although Darwin's theory of natural selection helped explain why certain genes imbued organisms with traits that enabled them to survive and reproduce, it did not answer the question of why nucleic acids combined in a certain way to create those genes.
"In the beginning of life, there was no time for natural selection," Ohno said. "They were all born because of natural law, not natural selection."
Comparing the genetic formulas of primeval protozoans to those of multicellular organisms such as fungi, animals and humans, Ohno arrived at the law that he believes governed the formation of genes, the theory of "repetitive recurrence."
On the surface, genes may appear to be composed of seemingly random assortments of the four nucleic acids--adenine, guanine, thymine and cytosine. But under close examination, the nucleic acids were found to recur periodically in the same order, sometimes in lengthy chains, other times in smaller combinations of links.
"It's like the way you decipher a cryptogram," Ohno said. "You look for the repeating units. . . . I think the first genes were all repeats of smaller units."
To crack these genetic codes, Ohno had to spend endless hours poring over chemical formulas, seeking a recurring pattern among the symbols, A, G, T and C, which represent the four nucleic acids.
Studying With Ears
In an effort to make his search a bit less tedious, Ohno decided one day to study with his ears instead of his eyes. A learned devotee of classical music, Ohno theorized that a lengthy sequence of nucleic acids occurring in the same order is much like a series of musical notes similarly arranged.
Because a classical composition typically consists of a main theme containing a certain sequence of notes, followed by a series of melodies based on that theme, Ohno concluded that one could "hear" the genes as a veritable symphony of nucleic acids sounding in a harmonic order.
Ohno's system for transcribing chemical formulas into musical movements is deceptively simple: Since there are eight notes in an octave scale, he assigned two consecutive notes to each of the four nucleic acids. For example, adenine would be represented by a D or E.
Such a rule allows Ohno great latitude in his efforts to turn nucleic acids into nocturnes. A series of nucleic acids provides him with a selection of notes with which to work, and he takes some liberties in determining the key, time signature and duration of notes for his chemical compositions.