(dramatic music) - I think Huntington's is unusually horrible.

It's so lethal, it just hunts you down.

At the time we were living in Los Angeles.

I used to like run on the beach, really fast and I thought, well, if I just run fast enough, I can cure my mom.

I had magical thinking even back then.

(gentle music) If you're a gene hunter, you want to have just gigantic families.

So our mission was to draw a family tree, because you have to really see who inherits the disease.

(gentle music) But now we have a family tree of over 18,000 people, in 10 generations.

These two families in Venezuela, in this little stilt village, right in the middle of nowhere, just deserved to be thanked.

Because all we know today, is thanks to them.

For myself personally, I decided not to get tested, until there's something that could actually make a difference in terms of treatment.

10 years ago, I said, "I think I have Huntington's then I said, "forget it", because you don't want to acknowledge that.

You know usually when I thought about it, I'd just burst into tears, because the idea of having Huntington's to me is awful.

(gentle music) Since I've been kind of the face of Huntington's for so long I went and got diagnosed.

I might as well admit it, and say well, guess what Nancy?

You do, you do have it.

When you know, lay awake at night, it sucks.

It's not a good feeling.

Thinking about it still, it takes my breath away.

It still makes me wanna cry.

It's not something I would have ever chosen.

But it chose me, so what do I do?

So, that's scary.

(gentle music) The data's fantastic.

It is so, optimistic, and so promising.

The cure for Huntington's is right there?

- Yep we just program the right order of the A, C, T and G's that we put together, to make this.

- That's shocking.

- The drugs that we want.

I have an example of what the finished product looks like.

It's just a little white powder like this.

- And when I held that magical vial, of course I'd like to just drink it myself, you know, why not?

(laughing) But when I held that vial, it was phenomenal.

Huntington's.

(laughing) You just happened to have that in your pocket.

(laughing) It's amazing.

That's my disease there, you're curing it.

I wanted to find a cure, so for my mom I wanted it.

For all the Venezuelans I want it still.

And for myself I want it.

I want all these things to be in time for me.

I think having that promise and that optimism, it is just totally magical, magical, magical.

(gentle music) - [Narrator] For more of Nancy Wexler's story, watch The Gene, an intimate history, beginning April 7th at eight, seven central, only on PBS.