Phenotype-associated patterns of cerebellar atrophy were detected; C9orf72 positive ALS-FTD patients exhibiting anterior lobe atrophy, bvFTD, and nfvPPA patients showing preferential posterior lobe volume loss, and patients with bvFTD demonstrating cerebellar crura degeneration and flocculonodular atrophy was observed in nfvPPA. Here, C9orf72 is linked to frontotemporal dementia.