These SNPs in the TMEM106B gene increase FTD risk and decrease the age of onset in people with heterozygous GRN loss of function mutations [43, 73], and while the evidence presented above suggests that higher TMEM106B sensitizes to dementia with ageing, reducing TMEM106B does not correct abnormal lysosomal enzyme activity and behavioural deficits in GRN+/− mice [74]. Here, GRN is linked to frontotemporal dementia.