Mukherjee is a cancer physician and researcher in stem cell biology. His previous book The Emperor of All Maladies: A Biography of Cancer won a Pulitzer Prize, while his research laboratory has identified genes that regulate stem cells, and genetic alterations in blood cancer.
In this book, he tells the story of the quest to decipher the code that makes us human, and the mechanism behind the code. It begins in 1856 when a monk first conceives of the existence of a 'unit of heredity', moves through Mendel and Darwin's theories, Nazi eugenics, Watson and Crick, to the recent discoveries and ethical dilemmas of gene therapy and CRISPR. He also relates the story of his own family's experience of hereditary mental illness which provides a very human counterpoint to the cerebral aspects of complex science, and reminds the reader that the relevance to our real lives is urgent.
This is a magisterial book, beautifully and precisely written. Mukherjee makes complex biological science accessible, and the challenging moral issues that come with this research profound and easy to grasp. A major achievement.