And in the middle of it all, agonizing over treatment protocols and watching his patients struggle with tremendous existential and physical pain, was the author himself.

Image Credit... Patricia Wall/The New York Times

There are far fewer psychological stakes in reading about the history of genetics. “The Gene” is more pedagogical than dramatic; as often as not, the stars of this story are molecules, not humans. Dr. Mukherjee still has a poignant personal connection to the material — mental illness has wrapped itself around his family tree like a stubborn vine, claiming two uncles and a cousin on his father’s side — but this book does not aim for the gut. It aims for the mind.

So what does this mean? That there are many excursions deep into the marshes of biochemistry and cellular biology. Bring your waders. It gets dense in there. Dr. Mukherjee can write with great clarity about difficult genetic concepts — he’s especially handy with metaphors — but the science gets increasingly complex, and it lasts for many pages. Even when the going is easy, readers should be prepared for parentheticals like this: “i.e., ACT CCT GGG –>ACU CCU GGG.”

Dr. Mukherjee’s explanations are sometimes so thorough they invite as many questions as they answer — from the most elementary (why is something that contains so many bases called deoxyribonucleic acid?) to the more esoteric (if, as he says in a Homeric footnote on Page 360, the Y chromosome is so unstable it might eventually disappear, will we still reproduce?)

I do not mean to suggest that Dr. Mukherjee has neglected to attend to big questions or ideas in this work; they just get lesser billing than I’d have liked. But any book about the history of something as elemental and miraculous as the gene is bound, at least indirectly, to tell the story of innovation itself. “The Gene” is filled with scientists who dreamed in breathtakingly lateral leaps.

Erwin Schrödinger in particular was one visionary cat: In 1944, he hazarded a guess about the molecular nature of the gene and decided it had to be a strand of code scribbled along the chromosome — which pretty much sums up the essence of DNA.

With each and every genetic discovery, a host of questions arose, both ethical and philosophical. What are the implications of cloning, of creating genetic hybrids, of gene editing? Is there any value in knowing about the existence of a slumbering, potentially lethal genetic mutation in your cells if nothing can be done about it? (Personally, I wish he’d dedicated 50 pages to this question — it’d have offered a potentially moving story line and a form of emotional engagement I badly craved.)