Very early-onset frontotemporal dementia with no family history predicts underlying fused in sarcoma pathology

Abstract

Sir, Neumann et al . (2009) recently described a new subtype of frontotemporal lobar degeneration (FTLD). They examined 15 cases of FTLD with inclusions that stained positive for ubiquitin (FTLD-U) but not transactive response DNA-binding protein (TDP-43), and found positive staining for the fused in sarcoma (FUS) protein in all cases. Interestingly, this case series was also characterized by an early age of onset and absence of family history. The mean age of onset was 38 years, and 12 out of the 15 cases had an age of onset of ≤40 years (Mackenzie et al. , 2008; Roeber et al. , 2008). Since this early age of onset is highly unusual for frontotemporal dementia (Neary et al. , 2005), we hypothesized that an age of onset at ≤40 years, in the absence of a family history, could also predict underlying FUS pathology. We tested this hypothesis by reviewing the Sydney Brain Bank. …