How one woman became the exception to her family’s Alzheimer’s history
A cruel twist of genetic fate brought Alzheimer’s disease to a sprawling Colombian family. But thanks to a second twist, one member of the clan, a woman, managed to evade the symptoms for decades. Her escape may hold the key to halting, or even preventing, Alzheimer’s. The inherited version of Alzheimer’s disease erodes people’s memories early, starting around age 40. In this family and others, a mutation in a gene called presenilin 1 eventually leaves its carriers profoundly confused and unable to care for themselves. Locals around the Colombian city of Medellín have a name for the condition: la bobera, or “the foolishness.” The woman in the afflicted family who somehow fended off the disease carried the same mutation that usually guarantees dementia. And her brain was filled with plaques formed by a sticky protein called amyloid. Many scientists view that accumulation as one of the earliest signs of the disease. Yet...