However, executive functioning is affected in all FTD genetic groups and clinical phenotypes,52 and it is shown that processing speed and executive functioning deficits seem early in presymptomatic familial FTD.39 Although we investigated modifying effects of TMEM106B in the largest collection of patients with systematically ascertained FTD and families from the ALLFTD study, generalization of our findings may be hampered as individuals in this study presented with high educational levels (mean of 15.88 years). Here, TMEM106B is linked to frontotemporal dementia.