The Gene: An Intimate History

by Siddhartha Mukherjee

The human genome contains about between twenty-one and twenty-three thousand genes that provide the master instructions to build, repair, and maintain humans.

Freaks became norms, and norms became extinct. Monster by monster, evolution advanced.

There is no such thing as perfection, only the relentless, thirsty matching of an organism to its environment. That is the engine that drives evolution.

Geographic isolation leads to genetic isolation, and to eventual reproductive isolation. This mechanism of speciation was not just conjecture; Dobzhansky could demonstrate it experimentally.

Hereditary messages were transmitted through a molecule, that molecule could exist in a chemical form outside a cell, and it was capable of carrying information from cell to cell, from organism to organism, and from parents to children.

Without equality, he argued, eugenics would degenerate into yet another mechanism by which the powerful could control the weak.

A gene is one line in a recipe that specifies an organism. The human genome is the recipe that specifies a human.