C9orf72 and behavioral variant of frontotemporal dementia: BvFTD with repeat expansions in C9orf72 (C9orf72-bvFTD) exhibits a higher degree of atrophy in parietal and occipital lobes, as well as the lateral inferior frontal lobe and cerebellum, compared with bvFTD carrying MAPT pathogenic variants (MAPT-bvFTD) and apparently sporadic bvFTD [4, 5].