KAREN DOUTHITT: Your grandmother has it. Your mom has it. Your uncle has it. Your aunts have it. Your cousin has it. I always assumed that I would have it.
HAMILTON: The disease moved front and center when the sisters learned that the mutation had been found in a close relative. Karen heard the news during a round of golf. She knew immediately that it greatly increased the risk that she and her siblings were carrying the mutation. HAMILTON: The sisters began raising money for the Alzheimer's Association, and they volunteered for Alzheimer's drug studies led by researchers at Washington University in St. Louis. All that happened seven years ago. This summer, I sat down with Karen and June again. They were attending the annual conference for families, this time in San Diego. Susie, the eldest sister, was there too, ready to join in a family discussion about some forms they had to fill out.
HAMILTON: The situation still worries little sister Karen, even though she's negative for the mutation. Late last year, she got some alarming news about her own health. She had breast cancer. But Karen says cancer doesn't leave you feeling helpless the way Alzheimer's does. HAMILTON: June has found some measure of solace by participating in Alzheimer's research studies. She knows the experimental drugs she's taking are unlikely to help her, but she hopes they'll lead to treatments that can make a difference to younger members of her family.