The clinical phenotype of C9ORF72-related FTLD has also been compared to FTLD cases carrying mutations in GRN and MAPT. In an early study, no clinical differences were seen between C9ORF72, GRN and MAPT cases, although neuroimaging showed predominant frontal atrophy was more common in the C9ORF72-related cases. This evidence concerns the gene GRN and Atrophy.