On the Origins of Modern Biology and the Fantastic: Part 7 — Robert A. Heinlein and DNA Replication

“Acting per se, like all art, is a process of abstracting, of retaining only significant detail. But in impersonation any detail can be significant.” – The Great Lorenzo, Double Star by Robert Heinlein

In Robert Anson Heinlein’s Double Star (1956), the down-on-his-luck actor “The Great Lorenzo” (aka Lawrence Smythe) is recruited by the frantic political team of John Bonforte, a VIP in solar system politics who has been kidnapped to cause a diplomatic crisis. Hired to impersonate Bonforte, over the course of a series of escalating complications, Smythe not only becomes sympathetic to Bonforte’s politics, but inhabits his role so perfectly that when Bonforte drops dead on election night, Smythe permanently becomes Bonforte. It is a light-hearted comedy about topics near and dear to its author’s heart—politics, space travel, moralizing, and shaving the numbers off of old tropes (in this case the classic body double plot)—that won the third ever Hugo Award for Best Novel and is widely regarded to be Heinlein’s best novel.

By 1956, Heinlein’s own Golden Age was in full swing, having “domesticated the future” for science fiction fans for the preceding twenty years through his straightforward prose and dedication to technical accuracy, making it easy for readers to visualize what a future among the stars might look like. John W. Campbell’s Astounding was the market paying generous (at the time) per word rates, enabling his contributors to make a living writing (provided they adhered to his domineering editorial vision), and the most successful writer in the Astounding stables by far was Heinlein. He would directly and indirectly pave the way for other writers to flourish in his wake, and for science fiction to flourish in general, becoming “worthy of adult readers and adult writers,” as Philip K. Dick put in a 1970 fan letter to Heinlein. As such, the story of the evolution of science fiction from its Golden Age origins is also the story of Robert Anson Heinlein.

Similarly, the discovery of the structure of DNA in 1953 represented a similar “domestication of the future” for biology, as it gave biologists a platform upon which working hypotheses could finally proliferate. Thanks to the influx of physicists and chemists into the field, it came at a time when the tools biology had at its disposal had become more sophisticated, thereby allowing scientists to ask more sophisticated questions. Because of this, no other science, not even physics, ever expanded as much as biology did in North America and Europe from the mid-1950s to the mid-1960s, leading to the expansion of labs, larger conferences, more competition, more conversation, and a proliferation of publications. And foremost among the questions being posed was how did this repetitive, double helical, “mirror image” molecule propagate itself from generation to generation and account for all the diversity around us?

Heinlein always claimed that the aim of his fiction was to get his readers to question everything, a tendency seemingly belied by his military background. Born in 1907 in Kansas City, Missouri to a large, impoverished Methodist family, he started work at a young age to support himself while reading everything he could at the public library, finding favorites among Horatio Alger stories, Mark Twain, and Rudyard Kipling. Aspiring to becoming an astronomer, his only option would be through entering military service; through hard work and persistence, he secured a spot at the U.S. Naval academy at Annapolis in 1924. In 1934, he was honorably discharged after contracting tuberculosis. Living in Los Angeles with the Great Depression in full swing, Heinlein became involved in the left-wing progressive End Poverty in California political movement, which aligned with his well already well-developed moral sense of social responsibility (he was also a lifelong nudist and non-monogamist, and associated with Jack Parsons—a famous rocket scientist and follower of Aleister Crowley, who was labeled a subversive by the military). But after Upton Sinclair’s failed bid for Governor and Heinlein’s own failed campaign for a seat on the State Assembly, in 1938, at the age of 31 and with only his military pension to pay the mortgage on their home and support him and his second wife, Leslyn, he turned to science fiction (having become a fan of the genre while in the Navy) to reach a wider audience with his ideas.

In the meantime, James Watson and Francis Crick’s 1953 paper “Molecular Structure of Nucleic Acids: a Structure for Deoxyribose Nucleic Acid,” included one of the biggest understatements in the history of biology: “It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.” The mechanism of copying DNA so that its nature would be conserved from cell to cell, generation to generation, is one of the two requirements of a hereditary material (other than being the blueprint of an organism). It is not uncommon in biology for form to imply function, and what Watson and Crick implied with their sentence is that for the hereditary material to be comprised of two perfectly complementary strands, one strand might act as the template for the other. If one were to separate the strands, any copies made would perfectly match its separated twin, indicating a ready mechanism for propagation. However, just as Watson and Crick’s model was only a theory in the absence of Rosalind Franklin’s X-Ray photographs to support it, so would the theory of DNA replication require experimental verification that would represent the beginnings of the field of molecular biology.

Heinlein’s career as a writer also contained a number of beginnings in science fiction. Campbell had only been full editor of Astounding for a few months before he bought Heinlein’s first story, “Life-Line” in 1938. Heinlein quickly learned to write to Campbell’s tastes and through correspondence over his stories, struck up what would become a lifelong friendship. Over the next twenty years, Heinlein wrote almost exclusively short fiction for the pulps (as they were the only venue for science fiction at the time), and published primarily with Campbell (selling his Campbell-rejected stories to less well-paying markets under various pen names). By the time America entered World War II, Heinlein was established as the central voice of science fiction, but he felt stifled by Campbell’s inflexibility when it came to taboo topics Heinlein wanted to write about—notably sex, religion, and non-monogamy. After volunteering for the war effort (acquiring a distaste for bureaucracy at the Philadelphia Naval Shipyard, but meeting his future third wife, Virginia “Ginny” Gerstenfeld), Heinlein set his sights on higher-paying markets and became the first to publish a science fiction story in a “slick,” selling “The Green Hills of Earth” to The Saturday Evening Post in 1947.

Another Heinlein first was writing and acting as technical consultant on the 1950 movie Destination Moon, the first modern science fiction film, which won an Oscar for its special effects, (the Hugo award statue is based on the rocket from the movie). But Heinlein’s most important legacy was bringing science fiction to the juveniles, where he took the adventure story into space, writing nine books between 1947 to 1959 filled with projections of his own childhood embodied in the resourceful, bootstrap-lifting boys with can-do attitudes who used logic and their internal moral compasses to overcome obstacles and see the galaxy—stories which had an enormous impact on the Boomer generation growing up reading them.

Just as impressively resourceful was the pair of biologists, Matthew Meselson and Franklin Stahl, who devised “the most beautiful experiment in biology.” At the heart of the question of DNA replication was the method: did the strands act as direct templates upon which copies were built (semi-conserved replication), or were the strands broken down and reassembled? Or perhaps they never separated at all (conserved replication) and were copied by some other mechanism? So, when Meselson and Stahl first met in 1954, they wondered if heavier radioactive isotopes could be used to tell the copies from the originals. The technique had been in use by biochemists for some time to track the products of enzyme reactions, but the question was how to separate such small molecules. It wasn’t until they were both working in Linus Pauling’s lab at Caltech in 1958 when Meselson heard about density gradient centrifugation, where a sample is added to a liquid gradient of different density salts and spun at high speeds until the samples descend to the corresponding density in the gradient. If they allowed DNA to replicate in the presence of radioisotopes, they could determine which was true: if there was one heavy labeled band, the parent strands were destroyed; if there was one heavy band and a light unlabeled band, replication was conserved; but if there was a heavy band and medium band, semi-conservative replication was true. The resulting pictures clearly showed a band in the middle. DNA replication, then, was semi-conservative—a beautiful confirmation of form denoting function.

While Meselson and Stahl were locked in a room by biophysicist Max Delbrück to write their paper on DNA replication in 1958, Heinlein was aspiring to his own alignment of form and function: namely, to use the platform of his fame to finally talk about the ideas editors had been resisting in his stories for decades. This came at a time when science fiction was changing—when paperbacks had become dominant, and readership was exploding (magazines had been largely done in by television and comic books during the ’50s)—and the Space Race was intensifying interest in science fiction. Unfortunately, Soviet successes with Sputnik and Yuri Gagarin, and events like the Cuban Missile crisis took their toll on Heinlein’s optimistic view that the world was inherently just and humanity would soon set out to explore the stars. While his ideas of individualism and self-responsibility remained prominent in his fiction, he became bitter over nuclear disarmament, believing the only solution was to carry the bigger stick and be willing to use it.

This lent the first novel of his middle period, Starship Troopers (1959), overtly fascist overtones (it nonetheless won the Hugo in 1960). Soon after, he wrote two other Hugo-winning novels—Stranger in a Strange Land (1960), a treatise on sexual freedom and self-responsibility, and the culmination of a decades-long attempt to write Mowgli as a Martian, and The Moon is a Harsh Mistress (1966), an homage to the American Revolution set in a Lunar anarchist utopia whose victory comes from flinging rocks at the earth until they grant their Independence. Thanks to the paperback trade, Heinlein became a bestselling author during this time, finding abundant new fans in the military, hippies, and libertarians alike. While Heinlein claimed his books were meant to challenge his readers’ beliefs without espousing any specific messages, Isaac Asimov said of Heinlein in his memoir, “He did not believe in doing his own thing and letting you do your thing. He had a definite feeling that he knew better and to lecture you into agreeing with him.” While his politics had always been apparent in his fiction, his writing in this period began to sacrifice plot and character in favor of a more didactic style. And whatever angle readers were coming from, science fiction and Robert Heinlein had become a part of the cultural lexicon.

While Meselson and Stahl were discussing radioisotopes, a researcher with extensive experience with the technique was approaching the question of DNA replication from his own different angle. Arthur Kornberg, a Polish-born biochemist at Washington University, took an Oswald Avery-like approach to identifying the cellular components necessary for DNA replication. Kornberg had expertise in enzyme purification and energy metabolism, and knew an enzyme was responsible, and energy was required for the replication process. He took bacterial cell extracts, added ATP (a small molecule used as energy in cellular reactions) and radioisotope-tagged nucleotides in order to track DNA assembly. He found a DNA-template was required as a “primer” (showing synthesis was not spontaneous), and subsequently purified the enzyme responsible, which he called DNA polymerase. Using this cocktail, he synthesized DNA from any number of sources, and—after a few short-sighted editors rejected his initial paper—it was accepted in 1958, and Kornberg won the Nobel Prize in 1959. His research group would later demonstrate that DNA made faithful copies that indeed ran complementary to one another, just as Watson and Crick’s model had predicted.

Heinlein’s late period begins in 1979 after a nearly decade-long hiatus, which included relocating to California, the building of a new house, and repeated bouts with various illnesses, including invasive surgery to correct a perforated bowel, which required a blood transfusion to keep Heinlein alive. The bulk of his efforts from the 1970s until his death centered around activist efforts to increase the pool of volunteer blood donors (particularly at science fiction conventions), as an advocate for the space program, and having his voice heard on the Reagan administration’s Citizens Advisory Board, where he threw his support behind the failed “Star Wars” strategic defense program. During this period, Heinlein wrote five novels, many of which were extensions of his future history series, except with an even stronger didactic style and a focus on the exploration of various sexual taboos, including incest. While his back catalog continued to sell well, Heinlein never returned to form, and after suffering complications from emphysema and congestive heart failure, Heinlein died at home in 1988 at age 81.

While DNA replication may seem like a minor corner of biology, but its importance can’t be overstated: the work in this area illuminated the basis of all genetic variation on earth. Any errors made during DNA replication could explain the spontaneous appearance of new traits in species. Coupled with selective pressure, DNA replication is the stuff of evolution. Not only that, but a revolution in biology occurred in 1983 when Kary Mullis, a chemist working at one of the first biotech companies, built upon Kornberg’s findings to replicate a specific region of DNA in a series of water baths with a technique called Polymerase Chain Reaction, allowing molecular biologists for the first time to copy specific regions of DNA. Mullis would win his own Nobel Prize for this work in 1993, and it is now a standard procedure used in every molecular biology lab around the world.

Heinlein’s legacy is far-reaching and multifaceted. He coined terms like astrogator, Waldo, and grok (to name a few), his juvenilia inspired a generation of engineers, scientists, and science fiction writers, and his middle-era books became the voice of a disaffected generation who was looking for something bigger to believe in—be it the protection and guidance of a strong military, and/or the freedom to live however individuals please in peace with one another. Reading his books today reveals a complete obliviousness to privilege, and an approach to writing female characters that attempts to be progressive but does not hold up at all well, getting bogged down in gendered stereotypes and objectification. It’s important to note, however, that he was thinking and writing about these topics often before there were national dialogues about them. Regardless of whether you agree with the politics or not, they’re books that inspire argument. Heinlein’s writing was the template against which science fiction writers and stories proliferated like so many complementary strands of DNA.

For our next article, we’ll see how another piece of the central dogma falls into place by exploring the relationship between DNA and RNA, and explore the life of another central figure in the Golden Era of science fiction: Isaac Asimov.

Kelly Lagor is a scientist by day and a science fiction writer by night. Her work has appeared at Tor.com and other places, and you can find her tweeting about all kinds of nonsense @klagor



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