The following cases from the Center for Neuropathology and Prion Research (Munich, Germany), Center for Neurodegenerative Disease Research (Philadelphia, USA) and Department of Neuropathology (Aalborg, Denmark) were included in the study: i) familial FTLD-U with linkage to chrom 9p (n=4), GRN (n=5), and VCP (n= 4) mutations; ii) FTLD-U either sporadic or familial with unknown genetic defect (subtype 1 (n=14); subtype 2 (n=19); subtype 3 (n=18) according to [33 (link)]); iii) ALS (n=18); iv) Tauopathies with concomitant TDP-43 pathology (AD+TDP-43 (n=3); CBD+TDP-43 (n=2). Cases of FTLD-U had a clinical diagnosis of the FTD spectrum (behavioural variant of FTD, progressive non-fluent aphasia, semantic dementia) with or without concomitant MND. Cases of ALS had clinical signs of MND with some of them developing cognitive changes only late in disease process. In addition, healthy controls (n=5), AD without TDP-43 pathology (n=5), CBD without TDP-43 (n=4) and TDP-43 negative FTLD-U cases (n=9) [31 (link)] were included. Demographic, clinical and neuropathological data are summarized in Table 1.