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In addition to the story we reported this afternoon, NPR's Jon Hamilton offers this report on another development in Alzheimer's research.
Finally, there's some good news about Alzheimer's disease. It turns out that a few lucky people carry a genetic mutation that greatly reduces their risk of getting the disease, an Icelandic team reports in the journal Nature . The mutation also seems to protect people who don't have Alzheimer's disease from the cognitive decline that typically occurs with age.