For the first time, researchers have identified a genetic form of late-in-life Alzheimer\u2019s disease \u2014 in people who inherit two copies of a worrisome gene.<\/p>\n\n\n\n
Scientists have long known a gene called APOE4 is one of many things that can increase people\u2019s risk for Alzheimer\u2019s, including simply getting older. The vast majority of Alzheimer\u2019s cases occur after age 65. But research published Monday suggests that for people who carry not one but two copies of the gene, it\u2019s more than a risk factor, it\u2019s an underlying cause of the mind-robbing disease.<\/p>\n\n\n\n
The findings mark a distinction with \u201cprofound implications,\u201d said Dr. Juan Fortea, who led the study the Sant Pau Research Institute in Barcelona, Spain.<\/p>\n\n\n\n
Among them: Symptoms can begin seven to 10 years sooner than in other older adults who develop Alzheimer\u2019s.<\/p>\n\n\n\n
An estimated 15% of Alzheimer\u2019s patients carry two copies of APOE4, meaning those cases \u201ccan be tracked back to a cause and the cause is in the genes,\u201d Fortea said. Until now, genetic forms of Alzheimer\u2019s were thought to be only types that strike at much younger ages<\/a> and account for less than 1% of all cases.<\/p>\n\n\n\n Scientists say the research makes it critical to develop treatments that target the APOE4 gene. Some doctors won\u2019t offer the only drug that has been shown to modestly slow the disease, Leqembi<\/a>, to people with the gene pair because they\u2019re especially prone to a dangerous side effect, said Dr. Reisa Sperling, a study coauthor at Harvard-affiliated Brigham and Women\u2019s Hospital in Boston.<\/p>\n\n\n\n