‘Drug Victory!’ ‘Cancer Defeated!’ ‘Breakthrough Discovery!’ Modern headlines sound like wartime dispatches from the frontline, as if doctors were spearheading a conquering army. Medical researchers have not always enjoyed such heroic status: in the middle of the 19th century, a statue of Edward Jenner – pioneer in the creation of a smallpox vaccine – was demoted from Trafalgar Square, deemed unfit to sit alongside the nation’s generals. But only a few decades later, drug manufacturers were characterising their products as troops of pith-helmeted soldiers storming through arteries to repel black bacterial demons, while individual scientists such as Louis Pasteur and Marie Skłodowska Curie were becoming iconic leaders in what was seen as the worldwide battle against disease.

Such triumphalism is misplaced: in medicine as in warfare, there are setbacks, missed opportunities and temporary setbacks. In his wonderful new book, The Song of the Cell, Siddhartha Mukherjee tells some marvellously gripping stories yet carefully avoids converting history into a rollcall of champions. In Mukherjee’s view, the formula for success is to be a ‘careful maverick’. As a cautionary tale about the dangers of racing to win the coveted accolade of ‘first’, he recounts the public shaming and subsequent imprisonment of He Jiankui, an ambitious Chinese investigator who was seduced by the lure of fame into the unlicensed and unwarranted gene-editing of embryos.

To illustrate the unfortunate turns often taken in medicine, Mukherjee relates the sad fate of the Hungarian obstetrician Ignaz Semmelweis, who in the 1840s dramatically reduced the death rates in his maternity wards by insisting that surgeons wash their hands in chlorinated water between carrying out an autopsy and examining a pregnant woman. Obvious as that advice now seems, other doctors refused to listen. Semmelweis was dismissed as a crank and confined to an asylum, while young mothers and their babies continued to die. Similarly, Gregor Mendel’s experiments on peas passed unnoticed for forty years before genes were identified. Conversely, coincidence and a keen eye for opportunity can fast-forward progress: ten years ago, a cancer cell treatment survived its first trial in Philadelphia after an enterprising physician gambled with an experimental drug that his own daughter happened to be taking.

Cells first became visible during the 17th century, when microscopes opened up a fascinating and formerly invisible world. In 1665, Samuel Pepys reported staying up all night, captivated by the detailed illustrations of plants and insects in Robert Hooke’s Micrographia, ‘the most ingenious book that ever I read in my life’. Likening the internal structure of cork to a honeycomb, Hooke introduced the word ‘cell’, but it languished unused until improvements in German optical technology enabled the next phase of cell biology to be launched in the 1830s. This development was far from inevitable: if a young lawyer called Matthias Schleiden had aimed better, the bullet he fired would have killed him rather than merely leaving him with a permanent scar on his face. Sometime after this suicide attempt, having turned his attention from law to the natural sciences, he teamed up with Theodor Schwann to demonstrate that all life is based on cells. This insight was soon taken further by Rudolf Virchow, a wise young man who told his father that ‘true knowledge is to be aware of one’s ignorance’. After electron microscopes entered laboratories in the 1930s, scientists could delve down even deeper and begin exploring how cells can work together. The latest gene-editing techniques operate on a smaller scale still, with scientists making changes equivalent to erasing a single word of a book in a library containing eighty thousand volumes.

Although cells are independent units, they cooperate to form integrated, functional living beings. Unravelling this interconnectedness is Mukherjee’s ultimate goal. In an inspired decision, he has constructed his book like an interlocking cellular creation: each of its six fundamental units – ‘Discovery’, ‘The One and the Many’, ‘Blood’, ‘Knowledge’, ‘Organs’, ‘Rebirth’ – can be read individually but they cohere perfectly as well. Scientific information is woven into stories of personal success and failure. Mukherjee comes across not only as a brilliant researcher but also as a deeply empathetic human being.

Novel ethical dilemmas have been opened up by scientific interventions at the cellular level. As Mukherjee points out, ‘every human is a stakeholder’ in the resulting debates and he feels that responsible citizens of the modern techno-scientific world should contemplate the questions thrown up by new medical developments. Many people (though certainly not all) would agree with Mukherjee about the benefits of taking steps before birth to prevent a painful disease or life-threatening malformation, but would it be right to use similar techniques to enable a person to grow taller or stronger? And what about pre-empting a condition that may or may not occur later, such as injecting a middle-aged person’s knee with revitalising stem cells before the first symptoms of osteoarthritis appear? Is it right to interfere with natural processes in this way?

Mukherjee ends by discussing an issue that lies within the domain of imminent reality. Sickle cell anaemia is a devastating inherited illness and trials suggest that treatment may be possible by re-engineering a patient’s own blood cells. But who would survive – would it be the same person or a different one? Such questions are of pressing concern. There may be no definitive answers, but this lively, thought-provoking book will help you consider them.