Study offers an explanation for why the APOE4 gene enhances Alzheimer’s risk March 4, 2021MIT The gene variant disrupts lipid metabolism, but in cell experiments the effects were reversed by choline One of the most significant genetic risk factors for developing Alzheimer’s disease is a gene called APOE4, which is carried by almost half of all Alzheimer’s patients. A new study from MIT shows that this gene has widespread effects on brain cells’ ability to metabolize lipids and respond to stress. In studies of human brain cells and yeast cells, the researchers found that the APOE4 gene significantly disrupts brain cells’ ability to carry out their normal functions. They also showed that treating these cells with extra choline, a widely available supplement that is considered safe for human use, could reverse many of these effects.