JOHN: NEARLY SEVEN MILLION AMERICANS CURRENTLY LIVE WITH ALZHEIMER'S -- AND BY 2060, EXPERTS SAY THAT NUMBER COULD BE AS HIGH AS 14 MILLION.

SCIENTISTS ARE TRYING TO FIND OUT HOW ONE MAN HAS BEEN ABLE TO STAVE OFF ALZHEIMER'S FOR 25 YEARS, DESPITE HAVING A RARE GENETIC MUTATION THAT, DOCTORS SAY, ESSENTIALLY GUARANTEED HE'D DEVELOP THE DISEASE BY HIS LATE 40'S OR EARLY 50'S.

ALI ROGIN SPOKE WITH PAM BELLUCK, HEALTH AND SCIENCE REPORTER FOR THE NEW YORK TIMES.

ALI: WELCOME BACK TO THE PROGRAM.

WHO IS THIS ONE MAN AND WHY IS HE PROVEN TO BE SO ESSENTIAL TO ALZHEIMER'S RESEARCH?

JONATHAN: DOUG WHITNEY IS A 76-YEAR-OLD WHO LIVES NEAR SEATTLE AND COMES FROM A FAMILY WHERE A LOT OF MEMBERS OF THE FAMILY HAVE INHERITED A RARE GENETIC MUTATION AND THE REASON WHY DOUG WHITNEY IS SO IMPORTANT IS HE ALSO HAS THE MUTATION, BUT HE HAS NOT DEVELOPED ALZHEIMER'S, AND HE IS ABOUT 25 YEARS PAST THE AGE WHERE IT WOULD HAVE BEEN EXPECTED FOR HIM TO DO SO.

SCIENTISTS AT WASHINGTON UNIVERSITY SCHOOL OF MEDICINE IN ST.

LOUIS WHO STUDY PEOPLE WITH THESE RARE MUTATIONS HAVE BEEN FOLLOWING HIM FOR 14 YEARS DOING ALL KINDS OF TESTS ON HIM, TRYING TO FIGURE OUT WHAT IS HIS BIOLOGICAL SECRET SAUCE PROTECTION -- PROTECTING HIM.

ALI: WHAT HAVE THEY FOUND OUT?

THEY HAVE BEEN STUDYING HIM, RUNNING TESTS, THEY HAVE GONE DOWN SOME AVENUES.

WHAT HAS BECOME CLEAR?

PAM: THE INTERESTING THING ABOUT HIM IS, ALZHEIMER'S DISEASE NOT ONLY THE RARE KIND BUT THE KIND THAT IS MUCH MORE WIDESPREAD HAS TWO PROTEINS THAT ARE HALLMARKS OF THE DISEASE.

ONE IS CALLED, LLOYD, THE -- ONE IS CALLED AMYLOID, THE PLAQUES THAT CLUMP IN THE BRAIN, USUALLY OCCURS SEVEN YEARS BEFORE AND THE SECOND IS TAU, THE ONE THAT FORMS STICKY TANGLES AND MUCH MORE CONNECTED TO SYMPTOMS OF COGNITIVE DECLINE.

SO WHAT THEY FOUND ABOUT DOUG WHITNEY IS, HE HAS A WHOLE LOT OF AMYLOID IN HIS BRAIN.

HE HAS AMYLOID LEVELS THAT SHOULD SUGGEST HE WOULD HAVE ALZHEIMER'S MANY YEARS AGO.

BUT HE HAS VERY, VERY LITTLE TAU .

SO SOMETHING IN HIS BIOLOGY HAS INTERRUPTED THAT PROGRESSION FROM AMYLOID PROTEIN TO TAU PROTEIN AND THAT IS WHAT THEY WANT TO ZERO IN ON.

THEY HAVE DISCOVERED SOME CLUES.

THEY DON'T HAVE THE EXACT ANSWER YET, BUT ONE OF THE MOST INTERESTING THINGS THEY FOUND IS, HE HAS A VERY HIGH LEVEL OF A DIFFERENT KIND OF PROTEIN CALLED A HEAT SHOCK PROTEIN.

PROTEINSTHAT FORM IN RESPONSE TO EXPOSURE TO HIGH HEAT AND SERVE A PURPOSE OF KEEPING OTHER KINDS OF PROTEINS THAT TEND TO GO OUT OF WHACK IN NEUROLOGICAL DISORDERS IN THE RIGHT FORMATION.

DOUG WHITNEY HAS A WHOLE LOT OF HEAT SHOCK PROTEINS.

WHY?

ONE REASON MIGHT BE, FOR ABOUT A DECADE HE WAS IN THE NAVY WORKING IN THE ENGINE ROOM OF A STEAM POWERED SHIP FOR MANY HOURS A DAY, EXPOSED TO SUCH HIGH HEAT THAT HE HAD TO BE HOSED DOWN DAILY AND THEY THANK THAT MAY HAVE DRIVEN HIS ACCUMULATION OF THESE HEAT SHOCK PROTEINS AND IF THAT WAS PROTECTING HIM THAT WOULD BE INSTRUCTIVE.

ALI: HOW WILL SCIENTISTS TRANSLATE WHAT THEY HAVE LEARNED ABOUT THIS SUPERHUMAN YET EVERYDAY GUY, INTO BROADER PROGRESS IN THE FIELD OF ALZHEIMER'S RESEARCH?

PAM: FIRST, THEY ARE TRYING TO LEARN MORE ABOUT WHAT ELSE MIGHT BE GOING ON IN HIS BIOLOGY.

THEY WILL BE LOOKING AT, ARE THERE OTHER PEOPLE WITH LOTS OF HEAT SHOCK PROTEINS THAT ALSO HAVE DELAYED ALZHEIMER'S.

CAN YOU RE-CREATE THESE EFFECTS IN THE LAB IN CELLS, IN ANIMALS?

CAN YOU FIGURE OUT WHAT EXACTLY IS THE THING CUTTING OFF THE PROGRESSION FROM THOSE AMYLOID PROTEINS TO THE TAU PROTEINS?

IF THEY DID DO THAT THAT WOULD BE HUGE BECAUSE IT COULD HELP INFORM THE DEVELOPMENT OF TREATMENTS THAT COULD DO EXACTLY THAT LONG BEFORE PEOPLE DEVELOP SYMPTOMS OF DEMENTIA.

WE HAVE VERY FEW DRUGS FOR ALZHEIMER'S AND THEY ALL WORK ON A CERTAIN PATH, KNOCKED DOWN AMYLOID.

SO FAR THEY HAVE BEEN SHOWN TO ONLY DO A LITTLE BIT, MAY BE SLOW DOWN THE DISEASE PROGRESSION FOR A SHORT AMOUNT OF TIME.

IF WE CAN FIND A WAY TO SAY, AMYLOID ACCUMULATION, WE DON'T NEED TO WORRY SO MUCH ABOUT THAT, BUT WE NEED TO CUT IT OFF BEFORE IT SPREADS INTO A TAU ACCUMULATION AND THEY CAN FIGURE OUT A DRUG TO DO THAT, THAT WOULD BE A TREMENDOUS ACHIEVEMENT.

ALI: THANK YOU SO MUCH.

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