Recent advancements in clinical chemistry have enabled precise quantification of AD biomarkers using plasma.5,6,7,8,9 The plasma Aβ42/40 ratio has revealed a promising discriminative performance for detecting Aβ positivity with good to excellent accuracy.10 Additionally, several epitopes of phosphorylated tau (p-tau),11,12,13,14 glial fibrillary acidic protein (GFAP),15,16,17 and neurofilament light chain (NfL)18,19 have been studied as promising plasma biomarkers for downstream AD processes, reflecting tau hyperphosphorylation, astrocytic activation, and neuronal damage, respectively. The gene discussed is GFAP; the disease is Alzheimer disease.