34 FTLD-FUS is characterised clinically by behavioural vari- ant frontotemporal dementia (bvFTD) and has a particularly young age of onset with a mean of 41 years. Further, this subtype had a high prevalence of psychotic symptoms (36% of cases) and low prevalence of motor symptoms (3% of cases). We did not ﬁnd FUS mutations in any aFTLD-U case. To date, the only subtype of cases reported to have ubiquitin-positive but tau-, TDP-43- and FUS-negative pathology, termed FTLD-UPS, is the result of charged multivesicular body protein 2B gene (CHMP2B) mutation. We identiﬁed three FTLD-UPS cases, which are negative for CHMP2B mutation, suggesting that the full complement of FTLD pathologies is yet to be elucidated. FTLD FUS FTLD-UPS Frontotemporal Keywords FTD Abbreviations bvFTD Behavioural variant FTD CHMP2B Charged multivesicular body protein 2B I. E. Holm Department of Pathology, Randers Hospital, Randers and Laboratory for Experimental Neuropathology, Danish Neuroscience Center, Aarhus University Hospital, Aarhus, Denmark D. W. Dickson R. Rademakers N. R. Graff-Radford Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA K. J. Hatanpaa C. L. White III Department of Pathology, University of Texas Southwestern Medical School, Dallas, TX, USA M. F. Weiner Departments of Psychiatry and Neurology, University of Texas Southwestern Medical School, Dallas, TX, USA F. Geser V. M. Van Deerlin J. Q. Trojanowski Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, USA B. L. Miller W. W. Seeley UCSF Department of Neurology, Memory and Aging Center, San Francisco, CA, USA J. van der Zee S. Kumar-Singh C. Van Broeckhoven VIB Department of Molecular Genetics, Neurodegenerative Brain Diseases Group, Antwerpen, Belgium J. van der Zee S. Kumar-Singh S. Engelborghs P. P. De Deyn C. Van Broeckhoven Institute Born-Bunge, University of Antwerp, Antwerpen, Belgium S. Engelborghs P. P. De Deyn Department of Neurology, Memory Clinic, ZNA Middelheim, Antwerpen, Belgium 123 FTD FTD-3 FTLD FTLD-IF FTLD-ni FTLD-TDP FTLD-UPS GRN MAPT NCI NII PPA TDP-43 VCP Acta Neuropathol (2010) 120:33–41 Frontotemporal dementia FTD linked to chromosome 3 Frontotemporal lobar degeneration Frontotemporal lobar degeneration with intermediate ﬁlament positive inclusions Frontotemporal lobar degeneration with no inclusions Frontotemporal lobar degeneration with TDP-43 positive inclusions Frontotemporal dementia with ubiquitin positive, TDP-43 negative inclusions Progranulin Microtubule associated protein tau Neuronal cytoplasmic inclusion Neuronal intranuclear inclusion Primary progressive aphasia Transactive response binding protein of 43 kDa Valosin containing protein E. H. Bigio Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA H.-X. Deng Department of Neurology and Clinical Neurosciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA G. M. Halliday Prince of Wales Medical Research Institute, University of New South Wales, Sydney, NSW, Australia J. J. Kril Disciplines of Medicine and Pathology, University of Sydney, Sydney, NSW, Australia D. G. Munoz Department of Pathology, Saint Michael’s Hospital, University of Toronto, Toronto, ON, Canada D. M. Mann Clinical Neuroscience Research Group, School of Translational Medicine, Greater Manchester Neurosciences Centre, University of Manchester, Salford, UK S. M. Pickering-Brown Clinical Neurosciences Research Group, Faculty of Human and Medical Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK V. Doodeman Department of Clinical Genetics, VU University Medical Center, Amsterdam, The Netherlands