LRRN3 and Alzheimer disease: We found that SAS‐1high‐MAS‐1low profiles, compared to SAS‐1low‐MAS‐1high profiles, are linked to two key protective features: elevated LRRN3 expression—a factor positively correlated with cortical gray matter thickness (CGMT), a marker of brain health and slower aging (Case Study 9a; Figure 8a)—and lower AD burden (Case Study 9b; Figure 8b–d).