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Medical tests can now reveal a person's risk for Alzheimer's disease, but taking those tests can be unsettling. NPR's Jon Hamilton saw that firsthand at a research center in Phoenix, where he spoke to people before and after they got their test results. The participants are identified by their first names only in order to protect their privacy.
JON HAMILTON, BYLINE: In a waiting room at the Banner Alzheimer's Institute, a woman named Rubie is about to learn whether she has a gene that puts her at risk for Alzheimer's.
RUBIE: Well, I'm a little apprehensive about it, and I hope I don't have it. But if I do, I want to be able to plan for my future.
HAMILTON: The gene is called APOE E4, and it's the most powerful known genetic risk factor for Alzheimer's in later life. APOE E4 doesn't cause the disease, but people who inherit even a single copy of the gene are at higher risk, and having two copies, one from each parent, amplifies that risk. Some studies have found that more than half of these people will develop Alzheimer's by age 85. Rubie is 74 and knows what the disease can do.
RUBIE: My mother had Alzheimer's in the last stage of her life, and I've got friends and family that have Alzheimer's.
HAMILTON: So Rubie volunteered for the Generation Program, which is testing an experimental drug meant to prevent or delay Alzheimer's. To qualify, you need to be between 60 and 75 and have two copies of the APOE E4 gene. Jessica Langbaum, a researcher at Banner, says finding out your genetic status takes courage.
JESSICA LANGBAUM: People are remarkably brave in stepping forward and raising their hands to participate in a study. But this is a big life decision for people to learn this information.
HAMILTON: So, Langbaum says, volunteers get a lot of education beforehand.
LANGBAUM: There are family considerations, there are emotional considerations, and there are insurance implications or considerations that people should think about before learning this information.
HAMILTON: Participants also talked to a genetics counselor at the University of Pennsylvania when they get their results.
LANGBAUM: We've really designed this study to also learn how to tell people this information about their genetic susceptibility.
HAMILTON: When Ruby talks to her counselor, she learns that she has a single copy of the APOE E4 gene. And she's OK with that.
RUBIE: I'm very glad to know.
UNIDENTIFIED PERSON: What?
RUBIE: Very glad to know. It takes the mystery out of it.
HAMILTON: For David, a retired businessman, the process is a bit more fraught. Before getting his results, he thinks he's prepared.
DAVID: I think I'm a big boy. I think I can handle it. If the testing comes out to where I'm running a higher risk, I think I'm going to put a lot more emphasis on enjoying the time that I have.
HAMILTON: But after learning his genetic status, he's concerned.
DAVID: I just texted my son. I said, are you home? We need to talk.
HAMILTON: David, like Rubie, learned that he has one copy of the APOE E4 gene. That's no big deal for him, but as he talked with the genetics counselor, he realized how the result might affect his adult children.
DAVID: My wife's grandmother and father both had Alzheimer's, and so the chances of her having an APOE E4 gene is very, very high.
HAMILTON: And that means David's children might be carrying two copies of the gene. He feels like his kids need to know his genetic status. But he's reluctant to tell his wife.
DAVID: She lived through that nightmare of her grandmother and her father passing away from Alzheimer's, and I think if she knew I even had that slight elevated risk, it could be very distressful to her.
HAMILTON: So David finds himself in a quandary.
DAVID: Fifty-five years of marriage - you've got to share stuff, but maybe some things are best not shared.
HAMILTON: Susan, who is 67 and runs her own business, has no qualms about sharing the test results with her husband, and they don't have kids. But Susan's parents both died with Alzheimer's, so she's afraid she'll learn that she has two copies of the APOE E4 gene.
SUSAN: When you're maybe 40 or 50, you don't want to face that fact. But, you know, once you're - once you've already hit 60, you go, you know, maybe I should know.
HAMILTON: Even so, Susan doesn't expect the test result to have an immediate impact.
SUSAN: I have yet to retire, though. I'm not - you know...
HAMILTON: Yeah, you said you're still working, so.
SUSAN: Yes. Yes, I'm even...
HAMILTON: If you found that you were very high-risk, do you think you would retire?
SUSAN: I don't think so.
HAMILTON: A bit later, Susan learns that she's carrying a single copy of the APOE E4 gene, and to her, that's great news.
SUSAN: I was pretty much prepared for the worst, you know. So, I mean, in a lot of ways, I feel like I won the lottery.
HAMILTON: And now she's sounding pretty certain about retiring.
SUSAN: Oh, I'll move ahead with it.
HAMILTON: Susan still hopes to work part time, perhaps at the Humane Society.
Jon Hamilton, NPR News, Phoenix.
(SOUNDBITE OF JAMES HEATHER'S "EMPIRE SOUNDS")