GFAP and Alzheimer disease: Importantly, cross-model validation using human AD organoids demonstrated conserved dysregulation of several key genes (CD44, CHL1, MSN, RGS7, GRIA1, CAMK2A, DLGAP1, GFAP) between postmortem brain tissue and organoid models, while also revealing model-specific differences that highlight both the utility and limitations of current in vitro systems for AD research.