The underlying pathology of FTD (termed frontotemporal lobar degeneration, FTLD) includes atrophy often most prominent in the frontal and temporal regions, together with the presence of degenerating neurons with intracellular inclusions that are immunopositive for either microtubule-associated protein tau (classed as FTLD-tau) or ubiquitin (FTLD-U). Here, MAPT is linked to frontotemporal dementia.