The Gene: An Intimate History

Known widely as the “father of genetics,” Johann Mendel was the son of peasants from Silesia (in modern-day Poland). Mendel joined an Augustinian abbey in Brno in 1843, was rechristened Gregor Johann, and was ordained as a monk in 1847. Mukherjee describes Mendel as “a short man with a serious face […] tending towards portliness” (18). The bespectacled, unassuming monk had little interest in the spiritual life, but the monastery provided him space and time to indulge his intellectual curiosity. The text stresses the early-career setbacks of Mendel to show his tenacity: The man who would be credited for one of the greatest discoveries in the field of biology twice failed to qualify as a school science teacher.

The text shows how two aspects of Mendel’s character informed his work: The first being Mendel’s willingness to experiment, and the second, the patience to “tend” to his experiments. Mendel’s genius lay in his instinctive understanding that sometimes “a profoundly artificial experiment” (53) was needed to reveal the underlying laws of nature. To reveal the laws of heredity, peas had to be bred for single traits (tall plant, white flower, and so on), pure-bred plants crossed to create hybrids, and the hybrids further crossed further. From the pea experiments, Mendel made his biggest contribution to genetics, the theory that an offspring inherited a unit of inheritance from each parent, and every trait it inherited was unitary—separate and distinct.

In the text’s symbolism around norms and mutants, Mukherjee paints Mendel as somewhat of an outlier himself, a man averse to populism or self-promotion. Mendel is so indifferent to making himself accessible that his groundbreaking paper was filled with mathematical tables and strange symbols. The paper would have proven “challenging even for statisticians. For biologists, it may have seemed like absolute mumbo jumbo” (53). After his work found little attention during his lifetime, Mendel moved away from science, though he continued to tend to his abbey and garden all his life. Mendel died of kidney failure in 1884.

Born in 1809 to a wealthy society doctor and his wife, Darwin is a towering figure in the field of biology. On the eve of the Beagle’s departure, Mukherjee describes the then 22-year-old Darwin as square-faced and handsome. As the Beagle travelled the world, Darwin’s job would be “collecting, observing, and noting any thing worthy to be noted in Natural History” (31). After his voyage concluded, Darwin and his team set to naming and classifying the fossils and remains they had meticulously collected over the years.

While the focus of natural history in Darwin’s day was taxonomy and classification, Darwin was more interested in the patterns that underlay the natural world. From the Beagle’s haul, he quickly unearthed two patterns: Species with common ancestry, and species splitting from each other. Having read Charles Lyell’s Principles of Geology that showed how rock formations were built by natural forces over time, Darwin wondered if a similar fate was at work in the biological world. He made an elaborate diagram of the model brewing in his head: Instead of all creation radiating outwards from God, he considered if nature forced species to diverge “like branches of a tree” (35). In 1850, Darwin published his theory of evolution in The Origin of the Species.



The radicalism of Darwin’s theory cannot be undermined, as suggesting that humans branched off from apes was nothing short of blasphemy. Nevertheless, it is a testament to Darwin’s integrity and intellectual curiosity that he persisted in his views.

Francis Galton is an ambiguous figure in the book, a brilliant man whose scientific ambition was muddled by a racist political agenda. Regarded as the father of eugenics, Galton was Darwin’s first cousin, younger than his eminent family member by 13 years. Mukherjee describes the young Galton as hungry to prove himself against the achievements of his cousin. Galton (like Mendel) faced setbacks in his early academic life, such as when a mental health episode kept him from appearing for an honors exam in Math at Cambridge.

Determined to prove his mettle, Galton began to study heredity on his own, though his enquiries took a radically different direction from Darwin’s. Instead of studying variation in animals and fossils, Galton embarked on studying variation in humans, an approach Mukherjee deems flawed because of its “top-down” nature, as it chooses for study the most complex organism and traits imaginable. In 1904, at a public lecture at the London School of Economics, Galton proposed eugenics, a breeding program for humans to produce only perfectly healthy, intelligent offspring.

Though Galton’s proposal sounds laughable in hindsight, Mukherjee notes how it gripped the popular imagination in the early half of the 20th century, soon leading entire nations to believe they could selectively breed a superior, “pure” race. Galton’s example is a cautionary tale about the dangers of making bad science a part of public policy.

The English biologist who coined the word “genetics” for the study of heredity and variation, William Bateson features as a prescient figure in the book, a counter to Francis Galton’s extremes. It was Bateson who rediscovered Mendel’s forgotten genius and evangelized it to the world, earning him the title “Mendel’s bulldog” (62). 

Described by Mukherjee as pugnacious-looking, Bateson was not just a fierce advocate for Mendel, but also one of first scientists who prophesized the misapplications of the future science of genetics. As early as 1905, decades before the rise of the Nazi party, Bateson wrote of the science of heredity being used by powers “to control the composition of a nation” (63). He also instinctively understood that if genes were particles of inheritance, they could be selected and purified independently of each other, leading to the augmentation of “desirable” genes and the elimination of “undesirable” traits.

The stars of genetics, Watson and Crick are presented as brilliant iconoclasts who shunned conventional methods to unveil the structure of the DNA molecule. Both were ambitious and unusual: Watson had trained as an ornithologist but moved to genetics; Crick was a former physics student with an unfinished PhD even at the age of 35. Crick would write that a “youthful arrogance, a ruthlessness, and an impatience with sloppy thinking” (147) came naturally to him and Watson. Though Crick calls the duo youthful, in truth he was 13 years older than the young Watson when they both became transfixed with the idea of discovering the structure of DNA.

Working together in Cambridge, the two talked as loudly as “children let loose in a playroom” (147), and were assigned a room to themselves. This “playful” aspect is important, since the genius of Watson and Crick’s approach was its childlike simplicity: They decided to build a physical model of DNA, figuring out its working through common sense. Informed by the works of chemist Linus Pauling, Watson and Crick already knew DNA was a coiled helix.

Mukherjee presents Watson and Crick’s construction of the model as a story of suspense, attempting to create narrative momentum in recounting their failures and successes. However, he does not shy away from the debts Watson and Crick owed other scientists, the first of those being Rosalind Franklin. Watson and Crick’s treatment of Franklin shows the dark side of the “ruthlessness” of which Crick was to write. Despite the ambiguity of some of their actions, Watson and Crick remain giants in science, their unveiling of the DNA double helix structure ushering in the next phase for genetics.

The neglected hero of the DNA story, the chemist Rosalind Franklin was only 38 when she died of ovarian cancer in 1958. Mukherjee describes Franklin as “dark-haired, dark-eyed […] with a gaze that bored through her listeners like X-rays” (144). One of the rare women in genetics during her time, Franklin’s unapologetic manner found her sidelined by some of the more sexist male members of London’s scientific scene. It was Franklin who discovered that the DNA molecule relaxed and stopped coiling in humid conditions, making its shadow infinitely easier to capture. Soon, Franklin was taking unprecedently clear photos of the shadows.

Though Franklin was close to visualizing the structure of the DNA molecule, Watson and Crick “won” the race, partly because Wilkins shared her work with the duo without consulting Franklin. Further, Mukherjee shows how scientists often undermined Franklin because of her gender. For instance, when Franklin gives a talk about her experiment at King’s in 1951, Watson, in the audience, is shown as hardly paying attention to her words, later writing that, “I wondered how she would look if she took off her glasses and did something novel with her hair” (149). An example of the neglect and sexism faced by women scientists in the mid-20th century, Franklin is finally being celebrated for her contributions to the discovery of DNA.