In recent years blood-based biomarkers for neurodegenerative illness have emerged (Teunissen et al., 2022), however, plasma biomarkers for AD [the ratio of 42 to 40 amino acid-long amyloid β (Aβ42/40) and tau phosphorylated at amino acid 181 (p-tau181)], astrocyte-expressed proteins [glial fibrillary acidic protein (GFAP)] and neurodegeneration [neurofilament light (NfL)] have limited utility in differentiating DLB from AD (Chouliaras et al., 2022; Gonzalez et al., 2022; Hamilton et al., 2023). Here, MAPT is linked to Alzheimer disease.