TMEM106B genotype (ie homozygosity for the minor allele) has been claimed to be a genetic modifier of FTLD in both GRN and C9ORF72 mutation carriers [25, 26, 28, 29], and to protect C9ORF72 carriers from FTD [25, 28, 29]. Here, TMEM106B is linked to frontotemporal dementia.