A study published in Nature Medicine on Monday reports that individuals with two copies of the APOE4 gene are "almost guaranteed" to develop Alzheimer's — if they live long enough.
Most Alzheimer's cases currently do not have an identifiable cause, with those carrying two copies of the APOE4 gene now believed to make up 15-20% of all cases but just 2-3% of the general population.
While frightening on the surface, this news is a boon to Alzheimer's researchers' efforts to find a cure. The identification of APOE4 as a singular cause of the disease in some individuals will unlock new treatments and spur research toward some of the most serious manifestations of the disease, such as early-onset Alzheimer's.
While this is promising research, we can't rely on genetics to solve the disease. Researchers are strongly warning people against APOE4 testing, as the fatalism could cause despair in patients. The scientific community should focus on proven, non-invasive lifestyle treatments, including diet and exercise.