Bill Gates has given millions of dollars to Alzheimer's research.

This is Jane Pauli.

Sunday mornings Dr. John LePook talks with Gates about his very personal reasons why,

and about a new treatment breakthrough that could be a game changer.

First of all, thank you so much for talking with me. Your father had Alzheimer's, and it strikes me that even being Bill Gates didn't protect your family from that.

Yeah, my dad in his late 80s had real effect of Alzheimer's.

In those last five years, he was quite limited.

He was lucky enough to have 24-hour care,

but there was no medicine, nothing that could bring his cognition back.

Was that one of the incentives for you to get into this?

Yeah, I mean, I'm super interested in health and as we get people to live longer,

unfortunately, a lot of those last years can be very low quality.

And so through my dad, the mysteries of why we've been able to avoid Alzheimer's, I got very curious about that.

And now the arc of this story is heading towards, well, maybe we can prevent Alzheimer's.

Yeah, I'm optimistic. You know, I put money into a number of areas, getting researchers to work together, a data platform,

really studying what causes the disease.

One of the bigger successes is we now have a blood diagnostic, so you can see if the amyloid which predicts you're on your way

to Alzheimer's that can be measured so recruiting people for trials is going to be a lot easier

now this decade if we keep funding the research we should have some fantastic tools, possibly not once

you get Alzheimer's, but to prevent some of the prevention tools are the most promising.

If we keep funding Alzheimer's, that's a big if.

How much have you already invested personally?

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