MAPT and tauopathy: Recently, Bieniek et al. [4] reported tau pathology in brains of individuals with FTLD associated with the C9ORF72 expansion mutation, but similar elevation of tauopathy were not observed in FTLD associated with GRN mutations suggesting that an overlap of FTLD-TDP and FTLD-Tau may occur in the context of C9ORF72. Interestingly, King et al. [29] reported an individual with an A239T sequence variant in the MAPT gene as well as the C9ORF72 expansion.