Over the weekend, I finished an excellent popular summary of genetics, The Gene: An Intimate History, by Siddhartha Mukherjee. It’s an excellent, thoughtful, current tome, that covers everything from Mendel to Darwin to Lysenko to Rosalind Franklin to CRISPR, written in a personal, accessible way. He begins and ends with a trip to India, examining the genetic roots of madness in his own family. There is a constant attention to the greater significance of the scientific insights — what they mean for society and individuals. It feels grounded and clear-headed as a result, and it’s never boring.

One thing I got from the book was a better appreciation for what eugenics was and is. Mukherjee tells some harrowing tales about the heyday of what he calls “negative” eugenics, the enforced sterilization that stains the early half of the last century in America – its motivations, adherents, and techniques. But the point then was to remove genetic information from the gene pool, hence the descriptor “negative,” quite independent of its negative impacts on human rights. He points out that we are now probably at the cusp of an era of “positive” eugenics, where we can add genetic information to our genomes, edit faulty alleles (changing our genomes), and even do this in a way that results in a permanent alteration of the human genetic line. It’s a different sort of thing from what “eugenics” usually implies, but it too is fraught with ethical concerns. Rather than depriving some sector of the populace of their human rights, the issues now have to do with access to therapy, unintended consequences, and the irrevocable step of finally taking the tiller to steer our own genetic destiny into what may eventually be a distinct species. Those concerns are always present in Mukherjee’s narrative, and he reminds us of them just often enough to keep them prominent in our reading experience, too.

The writing is probably the most extraordinary, exemplary thing about the book: it’s the sort of science writing we should all aspire to. It’s not a coincidence that Mukherjee’s previous book, The Emperor of All Maladies (a book about cancer) won the 2011 Pulitzer Prize. In a thousand small ways, Mukherjee demonstrates concepts with lucid prose and delightful flourishes. For instance, consider this quote, a minor example but one that is fresh in my mind from the final chapter:

Much of our knowledge of our genes and their function is inferred from similar-looking genes in yeast, worms, flies, and mice. As David Botstein writes, “Very few human genes have been studied directly.” Part of the task of the new genomics is to close the gap between mice and men — to determine how human genes function in the context of the human organism.

I love that – each sentence leads incrementally to the next; a clear explanation of a fundamental flaw in our understanding of our own genetics, and then there’s a subtle shout out to Steinbeck slipped in. No big deal made of it, it’s just elegant and leaves a brief tickle in the literary part of the reader’s brain. This book is full of pleasurable reading experiences like that.

If it’s been a while since you’ve thought about your DNA and how a tiny string of four nucleobases makes you who you are, then set aside some reading time over your winter break and indulge in The Gene.