GRN and frontotemporal dementia: Genome-wide association studies (GWAS) identified mutations of the TMEM106B gene as a major risk factor for frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP) [7, 8], which was mostly associated with the risk of FTLD-TDP in patients with progranulin (GRN) mutations [7, 9, 10].