This is corroborated by in vivo studies of patients with a straight filament 4-repeat tauopathy and clinical FTD resulting from MAPT mutations, showing binding in areas typically affected in FTD and affected at post-mortem (Bevan-Jones et al., 2016; Smith et al., 2016), and by the elevated binding in the affected brain regions of patients with svPPA (Bevan-Jones et al., 2018a, Makaretz et al., 2018) and bvFTD due to C9orf72 expansions (Bevan-Jones et al., 2018b), who have TDP-43 rather than tau pathology. This evidence concerns the gene C9orf72 and behavioral variant of frontotemporal dementia.