A large USC-led study found that the APOE ε4 gene variant — the strongest common genetic risk factor for late-onset Alzheimer's disease — may be linked differently to brain amyloid buildup in Hispanic older adults compared to non-Hispanic white older adults. Analyzing data from more than 17,000 participants across five major aging and Alzheimer's disease studies, researchers found that while APOE ε4 was associated with higher amyloid burden in both groups, the association was weaker among Hispanic participants. The findings suggest that cognitive impairment in Hispanic older adults may not always be driven by amyloid in the same way, and that other biological, vascular, or social factors may also contribute. The study underscores the need for more diverse populations in Alzheimer's research, particularly as anti-amyloid therapies become an increasingly central part of treatment.