The Gene

Siddhartha Mukherjee traces the gene as an idea — how it was conceived, contested, physically identified, decoded and eventually made editable — and argues that the ability to read and write heredity is one of the most consequential capabilities humans have acquired, with the ethical weight that implies.

The narrative runs from Mendel's peas and Darwin's problem of inheritance through the identification of DNA, the cracking of the genetic code, recombinant DNA, the Human Genome Project, and on to CRISPR and germline editing. Mukherjee's organising move is to show the word gene meaning something different at each stage: a unit of transmission, a physical stretch of chromosome, a code for a protein, a node in a regulatory network. Two threads run alongside the science. One is his own family's history of schizophrenia and bipolar illness, which gives the question of heritability a personal weight. The other is eugenics, treated at length as the historical demonstration of what follows when genetic determinism meets state power.

It suits readers approaching genomic testing, polygenic risk scores or gene therapies who want context before conclusions, and anyone interested in the ethics of editing inheritance.

On the evidence: as history and as ethics the book is rigorous and well-documented, and it is appropriately restrained about how much a genome predicts for an individual. One caveat is worth naming. An essay on epigenetics published around the book's release drew public criticism from working geneticists, who argued it overstated the role of epigenetic mechanisms such as chromatin modification relative to transcription factors in controlling gene expression. That dispute concerned a specific area, not the book as a whole. Read it for the conceptual and moral history, which is its strength; it is not a guide to interpreting your own genetic results.