We know when it's good, and we know when it's bad,

but there's a woman in Scotland -

- [Voiceover] I'm Joy Milne.

- [Narrator] Who can smell the unsmellable.

- [Voiceover] My nose went on fire.

- [Narrator] Joy Milne is the only known person

who can smell Parkinson's Disease.

- [Voiceover] I have an extremely sensitive sense of smell.

(sniffing)

I can smell it mainly on the forehead

and the back of the neck.

- [Narrator] To Joy, it has a greasy musky odor.

- [Voiceover] It is just a heavy smell to me.

- [Narrator] She first noticed it on her late husband,

Les Milne twelve years before he was diagnosed.

- [Voiceover] I just thought he was tired

and he wasn't showering enough.

It wasn't very welcome of course,

me saying to him, well, you're smelling.

- [Narrator] It wasn't until she attended a conference

with other Parkinson's patients that

she realized the smell was something more.

- [Voiceover] When I walked into the room I thought gosh,

these other people smell the same as Les does.

At the end of the meeting I stood up and said,

why were they not investigating the smell of Parkinson's.

- [Narrator] No one was investigating

because no one else could smell it.

Researchers set up a controlled experiment

to test Joy's nose.

She was asked to distinguish a set of t-shirts

worn by those with and without the disease.

She insisted one of the subjects

in the control group had the musky scent.

- [Voiceover] The man rang about eight months later

and said, “I've got Parkinson's.”

So, I had pre-diagnosed somebody.

- [Narrator] By the time most people are diagnosed

80 to 90 percent of the damage is done.

So Joy's mission is to help scientists

improve early detection methods.

- [Voiceover] If they can find these people earlier,

it would stop this anguish.

That would make such a difference.