GRN and neurodegenerative disease: GRN mutations, which are considered a major cause of familial frontotemporal lobar degeneration (FTD), explaining 25% of FTD cases worldwide [3-7], lead to the shortage of granulins, and GRN mutations are also found in other neurodegenerative diseases, such as Alzheimer’s disease (AD), corticobasal syndrome (CBS) and other atypical parkinsonian disorder (APD) patients [3, 8-13].