THE GENE: An Intimate History

James Gleick in The New York Times:

BookAs he did in his Pulitzer ­Prize-winning history of cancer, “The Emperor of All Maladies” (2010), Mukherjee views his subject panoptically, from a great and clarifying height, yet also intimately. Framing his story are pieces of his own family history: His cousin and two of his uncles “suffered from various unravelings of the mind,” and the specter of mental illness, presumably inherited or inheritable, haunts his family and his imagination. The books form a magnificent pair. “The Emperor of All Maladies” is, as Mukherjee notes, the story of the genetic code corrupted, tipping into malignancy. The new book, then, serves as its prequel. “Nothing about the natural world, at first glance, suggests the existence of a gene,” he writes. “Indeed, you have to perform rather bizarre experimental contortions to uncover the idea of discrete particles of inheritance.” The man who performed those bizarre contortions was the monk Gregor Mendel, living in an abbey in Brno, Austria-Hungary (now in the Czech Republic). The abbey had five acres of garden. Forbidden by the abbot to experiment on field mice, Mendel began growing peas. And he did not just plant them; he made hybrids, crossing tall plants with short plants, white flowers with purple flowers, smooth pods with crumpled pods. “He began to discern patterns in the data — unanticipated constancies, conserved ratios, numerical rhythms,” Mukherjee writes. “He had tapped, at last, into heredity’s inner logic.” After almost eight plodding years he wrote a paper, which he read in 1865 to a room of farmers and botanists in Brno and published in the yearly “Proceedings of the Brno Natural Science Society.” And then — nothing. The history of science is a tangled web, not a logical arc, and for four decades Mendel’s pioneering work — “the study that founded modern biology,” as Mukherjee describes with only a touch of hyperbole — effectively disappeared. The founding of modern biology had to wait till the turn of the century. Mendel’s forgotten paper was discovered by biologists in Amsterdam, Cambridge and elsewhere. Mendel had discovered the basic unit of heredity, had proved there must be such a unit, and finally a Danish botanist, Wilhelm Johannsen, gave it a name: “gene,” he suggested — “a very applicable little word.”

What is the gene? First it was an abstraction, an enigma, “a ghost lurking in the biological machine,” Mukherjee writes. By definition the gene was the carrier of any trait that is heritable or partly heritable. One would say there are genes for eye color, height or even intelligence. But some traits are better defined than others. People have long bred dogs, for example, to be “short-haired, longhaired, pied, piebald, bowlegged, hairless, crop-tailed, vicious, mild-mannered, diffident, guarded, belligerent.”

More here.