Among others, Granulin (GRN) mutations, inducing a loss of 50% functional Progranulin [9,10], are present in a proportion of patients whose most typical clinical presentations include the behavioral variant of Frontotemporal Dementia (bvFTD) and the agrammatic variant of Primary Progressive Aphasia (avPPA). The gene discussed is GRN; the disease is frontotemporal dementia.