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Open any molecular biology textbook, and even the most casual reader will be assaulted by facts. You’ll learn that DNA is composed of four nucleotides and arranged in a triplet code. You’ll read about the central dogma (DNA to RNA to protein, with some exceptions) in extraordinary detail, and perhaps you’ll learn what certain proteins do, or fail to do in various disease states. But what’s often missing is the complex human narrative of how these truths were discovered. The messiness of science, with its dogmatic stalwarts, intellectual battles, transformational experiments and unsung heroes are hidden behind simplified figures and colorful diagrams. For a textbook, this un-dramatic clarity is largely the point, and is essential for students, young and old, as a steady reference. Still, it’s probable that this general lack of human context is a reason why the very term textbook is synonymous with dry and dense reading; the intellectual equivalent of plain oatmeal. Good for you, but not inherently very appetizing.

On the other hand, there are works like Horace Freeland Judson’s masterpiece The Eighth Day of Creation, which traces the staggering human drama, with all its heartbreak and triumph, of the early history of molecular biology. Books such as these, and there have been many, present the human context brilliantly if at the expense of becoming dated (The Eighth Day ends around 1975), of bringing you up to speed in a particular field, or of having an overall scientific thesis to communicate.

The middle ground, part textbook and part history, thus presents a considerable challenge. RNA: Life’s Indispensible Molecule, by Rockefeller University (RU) emeritus professor James Darnell, meets that challenge forcefully. Dr. Darnell, most well known by undergraduates as a textbook author of Molecular Cell Biology, wields his textbook writing skills fluidly into a human narrative of the history of RNA. The result is “an unapologetically historical” account of RNA research, refreshing in its use of primary data for the majority of figures and for the rigorous treatment of historically important experiments from one of the giants of the field. The experience is one of an exceptional and nuanced guided tour, and as Dr. Darnell tells the story, is infused with many first-hand accounts of great scientific moments. This added context adds unique depth to many well-known stories on the early biochemical research of DNA and protein, and offers a suitable introduction of RNA as the key mediator between the two. After summarizing the early days of molecular biology, Dr. Darnell weaves a compact—though never too dense (ie sleep inducing)—historical narrative, plumbing his own rich history in RNA research. One gets the sense that Dr. Darnell’s passion for RNA stems from both scientific interest as much as the people who did the work: old friends, colleagues, and even former competitors, are liberally credited throughout, oftentimes with palpable warmth.

The emphasis on RNA given Dr. Darnell’s career would only mistakenly appear biased at first glance as it serves an important purpose. For Dr. Darnell, an underlying theme in charting the course of biology in the twentieth century highlights how researchers’ thinking was shaped by the technology and experiments they could perform. For this reason, late nineteenth and early twentieth centuries chemists and early biochemists were most interested in proteins, whose 20 plus amino acid variations appeared to offer the appropriately complex platform to organize the physical and informational structures of life. Nucleic acids, difficult to study and seemingly less complex, remained an intellectual backwater until Avery, the phage group, and Watson and Crick ushered in the molecular biology revolution. With the resulting emphasis on the informational primacy of DNA from the 1950s onward, RNA was initially cast as the “adapter,” a fragile and cryptically simple link between the master blueprint in DNA and the structures of proteins, the key “doers” of the cell. Dr. Darnell upends this notion by showcasing a history of RNA as the centerpiece of molecular biology, hidden as it was to many of its early practitioners, and only slowly revealed with new tools and assays over the past 40 years. Chapters three and four offer a concise though detailed summary of pioneering experiments done in bacteria that led to tRNA and RNA polymerase, and experiments done in mammalian cells to establish ribosomal function and mRNA architecture through the 1970s and 1980s. Chapter five, the longest and most-textbook like, attempts to summarize RNA research post 1990, which is admittedly a tall order, though by focusing on mRNA regulation, Dr. Darnell manages to convey a rich story that touches on the most important aspects that sustain researchers to this day. For a thorough introduction on the major players and themes of current RNA research, you’d be hard-pressed to find a better example under a hundred pages.

The final chapter, while rooted in conjecture, offers many gems to ponder. As Dr. Darnell points out, given the existence of RNA genomes and RNAs with enzymatic activity, in principle one could do away with DNA (as an information carrier) and protein (as an enzymatic machine) entirely. This final chapter ferries this point to its conclusion by discussing the basis for the “RNA world” hypothesis. Though almost mystical in scope, Dr. Darnell never strays from the scientific basis of positing early life as evolving from self replicating RNAs, and outlines the incomplete state of current research directed towards finding life’s origin. It’s an expansive note to end on; certainly one that leaves many questions for future RNA scientists to explore.

“Why the furor over DNA and protein?” Dr. Darnell asks. He continues, “they are both simply the handmaidens that have allowed RNA to have its way with this planet.” This statement, which closes the book (and graces the back cover) shouldn’t be much of a spoiler given the title. In fact, if that’s all one read, it could rightly be taken as over-the-top. Only after traversing a rich history of both cells and people, with Dr. Darnell as a spirited guide, does this sentiment not only seem plausible, it is warranted.