GRN and frontotemporal dementia: To further explore the relationship between GRN insufficiency and protein homeostasis abnormalities, we created i3Neurons from an FTD patient-derived iPSC line with a heterozygous GRN mutation [35] (c.26 C > A, p.A9D; referred subsequently as ptMut), as well as the isogenic iPSC control line with corrected GRN mutation (ptWT).