The heart is a lonely hunter. Also it’s the organ in your chest that pumps blood through your veins and arteries.

An old metaphor ran up against new medicine in 1982 when Dr. William DeVries performed the first artificial-heart transplant on patient Barney Clark, who lived 112 days with the battery-powered pumper. A stunning media circus ensued, with the Frankenstein factor riling many Americans, as cutting-edge technology was introduced before old dreams and superstitions had been put to rest. “I was surprised that people think it’s as big a deal as they think it is,” DeVries said later in the year.

Far thornier questions about reimagining nature are close at hand as our greater understanding of genetics promises to allow us to drive evolution. Let’s hope this time the debate is more rational, since the application of such information will have profound implications–for good and ill.

There’ll be the opportunity to “delete” sicknesses preemptively and the temptation to improve upon what’s already basically fine. If Homo sapiens isn’t done in first by a cold war or a heat wave, then we’ll almost definitely explore “human enhancement,” and these experiments will likely be decentralized, with not only states and corporations competing but also startups in garages.

In a conversation with David Remnick on the New Yorker Radio Hour, Dr. Siddhartha Mukherjee, a great science writer as well as a cancer specialist, talks about the gene, which he calls, in his most recent book, “one of the most powerful and dangerous ideas in the history of all of science.” The host offers that new genetic knowledge has greater game-changing potential than the splitting of the atom–and the games will likely be messy and possibly dangerous. In fact, they’ve already begun.

An excerpt:

Siddhartha Mukherjee:

I draw a formal analogy between those two moments. The splitting of the atom really opened up the possibility of controlling energy and matter, so that opened up an immense technological possibility full of promise and peril. The promise being nuclear technology, the peril being Fukushima. 

The genome also opens up that idea of promise and peril. The promise being the curing of deadly diseases, the early diagnosis of breast cancer, the capacity of being able to predict, in our children, those that will carry devastating mutations that will make them, potentially, have lives of extraordinary suffering. 

But the peril is also questions of identity. What if we learn, and we are going to learn, not about one gene but multiple genes that govern sexual identity? What if we learn about genes that predispose to illness but don’t cause extraordinary suffering?

David Remnick:

And the decisions to abort or not abort that would come along with it.

Siddhartha Mukherjee:

That’s right. And just to give you one example, this is not fantasy: In India and China, based on very crude genetic diagnosis, whether you’re a boy or girl, that phenomenon is already in action and has skewed the selective abortion of those diagnosed genetically as female…has skewed the gender ratio in Indian and China to something absurd, 700 women to 1,000 men, in some parts of India and similarly in some parts of China. 

David Remnick:

So the tragic mistakes are already being made at an early stage.

Siddhartha Mukherjee:

That’s right. The tragedy is not tomorrow’s tragedy. It is today’s tragedy. In fact, it’s yesterday’s tragedy. Those societies have already been destabilized by genetics.•