APOE and Alzheimer disease: In this study, we have comprehensively investigated genome‐wide landscape of RNA‐editing events from 4208 (1364 AD cases vs. 742 healthy controls) RNA‐seq samples across nine human brain regions from three large biobanks (MSBB, MAYO, ROSMAP), including sex‐specific and APOE4‐specific manner adjusting for age, PMI, sex, and APOE4 status.