Sanjay Gupta

And these circus performers, they could do all kinds of things.

They could take sharp objects and put them through their hand, and they could walk on hot coal and do all this sort of stuff, which they had seen before.

But the difference with this particular family, for instance, when they were walking on hot coals, was that they could feel the coals.

And they could feel that they were hot.

So they had sensation and they had pretty significantly preserved hot, cold sensation.

What they did not have was pain.

That's the only thing.

So a lot of other firewalkers, for example, they just don't feel anything.

They're sort of insensate or numb to it.

They weren't insensate.

So that was really interesting.

And they found that, in fact, it was this 14-year-old boy that they first met, but then it was the whole family that seemed to be able to do this.

They identified a gene, which they expected to find.

And that gene, I think, is SCN9.

It's a sodium channel blocker.

So the way that we conduct signals around our body is by changing voltages and sodium channels.

So this is a particular sodium channel blocker that they decided to essentially try and replicate through a medication.

And this is Vertex Pharmaceuticals, which many of your listeners may know this company.

But basically for a quarter century, they just were working on this drug, which was essentially trying to replicate what that gene did for that family in Karachi, Pakistan, to sort of take away pain without dulling everything, without making someone insensate or numb.

And it worked.