From leading geopolitical expert and technology futurist Jamie Metzl comes a groundbreaking exploration of the many ways genetic engineering is shaking the core foundations of our lives-sex, war, love, and death. At the dawn of the genetics revolution, our DNA is becoming as readable, writable, and hackable as our information technology. But as humanity starts retooling our own genetic code, the choices we make today will be the difference between realizing breathtaking advances in human well-being and descending into a dangerous and potentially deadly genetic arms race.

In November 2018, the world was shocked to learn that two babies had been born in China with DNA edited while they were embryos - as dramatic a development in genetics as the cloning of Dolly the sheep was in 1996. In this book, Hank Greely, a leading authority on law and genetics, tells the fascinating story of this human experiment and its consequences. Greely explains what Chinese scientist He Jiankui did, how he did it, and how the public and other scientists learned about and reacted to this unprecedented genetic intervention. 

Not since the atomic bomb has a technology so alarmed its inventors that they warned the world about its use. Not, that is, until the spring of 2015, when biologist Jennifer Doudna called for a worldwide moratorium on the use of the new gene-editing tool CRISPR - a revolutionary new technology that she helped create - to make heritable changes in human embryos.

The burgeoning new science of epigenetics offers a cornucopia of insights - some comforting, some frightening. For example, the male fetus may be especially vulnerable to certain common chemicals in our environment, in ways that damage not only his own sperm but also the sperm of his sons. And it’s epigenetics that causes identical twins to vary widely in their susceptibility to dementia and cancer. But here’s the good news: unlike mutations, epigenetic effects are reversible. Indeed, epigenetic engineering is the future of medicine.

John's medical memoir was born from chaotic, disjointed, funny and frightening late-night letters to friends over email (any recipients of which all those years ago will likely walk away now). Those manic blogs from the hospital wards during under-slept call nights (which left a few friends wondering if he had invaded the hospital pharmacy) were the genesis for this book, Playing Doctor.