Scientists studying a Colombian family plagued by early-in-life Alzheimer's have found a rare gene variant that seems to delay initial symptoms by about five years. The first clue came from a woman who escaped her family's genetic fate, apparently because she also had two copies of a different mutated gene that shielded her. Now researchers have found one copy of that variant was enough to delay disease onset in 27 other members of that family. If they learn how the protection works, it could lead to novel treatments. The finding was published Wednesday in the New England Journal of Medicine.
