In 2011, Indian-American oncologist and writer Siddhartha Mukherjee won a Pulitzer Prize for "The Emperor of All Maladies," his panoramic history of cancer. His new offering, "The Gene," is equally authoritative, building on extensive research and erudition, and examining the Gordian knots of genes through the prism of his own family's struggle with a disease. He renders complex science with a novelist's skill for conjuring real lives, seismic events.

"The Gene" opens in 2012 as Mukherjee, a professor at Columbia University in New York, traveled with his father to Calcutta to visit his cousin Moni, institutionalized for mental illness. Moni had long exhibited behavioral tics and mood swings similar to those of other relatives, leading Mukherjee to suspect an inherited trait.

Here he captures Moni's humanity with customary lyricism: "The most striking thing about his illness, though, was not the storm within his mind, but the lull in his eyes. The word moni means 'gem' in Bengali, but in common usage it also refers to something ineffably beautiful: the shining pinpricks of light in each eye. But this, precisely, is what had gone missing in Moni."

That lack inspired Mukherjee to chart the arc of genetics, from Aristotle's investigations to Gregor Mendel's legendary pea plants to a horrific eugenics vogue that culminated with the Nazis' barbaric experiments in Auschwitz.

Mukherjee hits all of his high points — the dramatic double helix story, early technologies that peered deeper into DNA — as he guides us from lab to lab. He reaches a crescendo with the multinational Human Genome Project, tasked with sequencing the arrangement of A, T, C and G, and its two antagonists, privately funded cowboy geneticist Craig Venter and the HGP's buttoned-up head, Francis Collins. (Venter and Collins crossed the 10-year finish line in a virtual tie, announcing their results at a 2000 White House press conference with President Bill Clinton.)

Despite the book's elegant craftsmanship, some technical sections will lose lay readers, particularly among the dense thickets of his later chapters, as Mukherjee delves into thrilling recent developments in gene therapy, epigenetics and gene "editing." Sometimes the specifics can't be dumbed down for the rest of us, despite a beautiful prose style.

Mukherjee seems focused on this problem, though, and seasons in lively anecdotes and characters, such as Huntington's researcher Nancy Wexler's fieldwork in Venezuela, and the urgent debates surrounding the biological underpinning of gender identity.

In the end he evokes his father again, in a coda that speaks to the poetry of our web of life: "Abhed, my father had called genes, 'indivisible.' … Scientists divide. We discriminate. It is the inevitable occupational hazard of our profession that we must break the world into its constituent parts — genes, atoms, bytes, before making it whole again. … But there is a hazard implicit in this method. Once we perceive organisms — humans — as assemblages built from genes, environments and gene-environment interactions, our view of humans is fundamentally changed."

Hamilton Cain is the author of "This Boy's Faith: Notes From a Southern Baptist Upbringing." He lives in Brooklyn, N.Y.