Peripheral cells (lymphoblasts) isolated from GRN mutation-carrier (c.709-1G > A) with TDP43-positive FTD patients showed that GRN haploinsufficiency stimulated NFkappaB signaling and overactivated Wnt5a signaling, leading to increased intracellular Wnt5a levels and Wnt5a secretion. Here, GRN is linked to frontotemporal dementia.