Since the landmark discovery of the RNA/DNA binding protein, TDP-43, as the main constituent of ubiquitin-positive, tau/synuclein-negative inclusions in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) referred to as FTLD-TDP [1], there have been numerous advances in our understanding of these seemingly disparate clinical and neuropathological syndromes (reviewed in [2]). This evidence concerns the gene TARDBP and frontotemporal dementia.