TL;DR
The strongest common genetic risk for Alzheimer's disease is a gene variant called APOE4. A small study from the University of Missouri points to a drug that could one day be aimed squarely at them. Four weeks of low-dose rapamycin, one of the longevity field's most-watched bets on slowing aging itself, improved blood flow in the brains of healthy middle-aged APOE4 carriers, but not in people without the variant. Women carrying APOE4 improved the most. It is an early pilot with no placebo group and no memory test, and its real value is a map: it suggests who should be first in line when rapamycin is tested for protecting the aging brain. To see our odds on when a rapamycin study shows a memory benefit, and the timeline of breakthroughs that leads there, subscribe.
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