Although it would be important in future studies to assay the role of mR-129-5p in iPSC-derived neuronal and glial cells from patients with C9ORF72, GRN or MAPT mutations, these data clearly show that lower miR-129-5p levels in astrocytes are sufficient to cause neuronal phenotypes observed in FTD. Here, GRN is linked to frontotemporal dementia.