The Biomarker Core will contribute to the ADRC by overseeing research activities involving fluid (and tissue) biomarkers, neuroimaging and DNA. Biomarkers are critically important as indicators of pathology, structure and pathophysiology of brain changes in Alzheimer’s Disease and Related Disorders (ADRD). In Alzheimer’s, the Amyloid, Tau, neurodegeneration (ATN) framework uses biomarkers to stage disease. Biomarkers can help with diagnosis, including revealing pathological changes during preclinical or early stages of disease. They can help with differential diagnosis, prognosis, and identification of disease heterogeneity. For fluid biomarkers, the ADRC will collect blood (for DNA, plasma, serum) annually, cerebrospinal fluid (CSF) at baseline on as many participants as possible (and repeated after 24 months), research MRI on as many participants as possible at baseline, and amyloid and tau PET on at least 24 participants per year plus 10-20 more through the CLARiTI project. For fluid biomarkers, the Core will maintain a repository where collected samples are stored. Biomarkers will be measured in CSF to assess ATN, and emerging plasma biomarkers will be measured at UCSD and using resources of the NCRAD laboratory that serves the entire ADRC network. For α-Synuclein, seeding amplification assays will be obtained in CSF, and from serum or plasma if new methods become standardized. DNA will be prepared at the ADRC and also at NCRAD from samples that will be shared. APOE genotyping, GWAS and other genetic sequencing will be performed, coordinated by NCRAD. Research MRI imaging will be obtained using standardized sequences, in compliance with the SCAN project. To characterize amyloid burden, amyloid PET will use florbetapir, and for tau burden, tau PET will be obtained with MK6240. MRI and PET data will be shared with the SCAN project. Vascular disease due to arteriosclerosis and amyloid angiopathy will be assessed through MRI. The Biomarker Core will use stringent quality control to ensure that acquisition of samples and imaging follows best practices, and will maintain rigor in analyzing biomarker data. The Biomarker Core will conduct and support additional research to identify novel biomarkers, including sharing samples with outside investigators. Core faculty will assist in teaching activities for REC and other scholars and will provide advice to investigators who wish to use biomarkers in new grant applications.