Biomarkers for AD should, thus, reflect the core pathogenic findings in the brain, i.e. plaque and tangle pathology, as well as the associated pathophysiological mechanisms, i.e. axonal and synaptic degeneration (Box 1) and frequent co-pathologies, including TDP-43 and α-synuclein pathologies (see poster, ‘Brain imaging’). Here, TARDBP is linked to Alzheimer disease.