A recent study conducted by researchers in Nature Medicine has highlighted the potential risks of a genetic variant of the Alzheimer's risk gene APOE4. Titled "APOE4 Homozygosity Represents a Unique Genetic Form of Alzheimer's Disease," the study reveals that individuals carrying two copies of the Alzheimer's risk gene APOE4 are more likely to exhibit biological indicators of Alzheimer's pathology in the brain, as well as biomarkers of the disease in cerebrospinal fluid and PET scans.