GRN and obsessive-compulsive disorder: While Grn homozygous null (Grn−/−) mice are viable and fertile, they exhibit several features of FTLD-GRN and CLN11 including lysosomal dysregulation, lipofuscinosis, neuroinflammation, synaptic loss, retinal ganglion cell (RGC) loss, and obsessive compulsive disorder (OCD)-like behavior as well as social deficits [16, 88, 137, 174–177] and therefore have been widely used as a model of FTLD-GRN and CLN11.