Distinct Clinical Characteristics of C9orf72 Expansion Carriers Compared With GRN, MAPT, and Nonmutation Carriers in a Flanders-Belgian FTLD Cohort

Clinical features ofTBK1carriers compared withC9orf72,GRNand non-mutation carriers in a Belgian cohort

“…Only one of the TBK1 carriers was diagnosed with FTD-ALS, preventing a genotype–phenotype comparison with FTD-ALS patients carrying a C9orf7 2 expansion mutation. ALS occurred in the current study in 23.1% of the C9orf72 carriers in the Belgian FTD cohort, a similar result as the previous observation of 27% by Van Langenhove et al (2013) . In the same FTD cohort, none of the GRN carriers had ALS.…”

Diversity of Cognitive Phenotypes Associated with C9ORF72 Hexanucleotide Expansion

“…In our series, the common factors in the non-FTLD cases were a strong family history of dementia or psychiatric disease and the presence of frontotemporal atrophy on neuroimaging; however, we were biased to analyze cases with these features. The cases with defined FTLD syndromes had a younger age at onset than the C9-negative cases, and their main phenotypes were primary progressive aphasia or behavioral variant converging with disease progression, in agreement with previous reports [18–23]. Associated features in our cases included symmetric parkinsonism, corticobasal degeneration features, and psychiatric symptoms.…”

Extended FTLD pedigree segregating a Belgian GRN-null mutation: neuropathological heterogeneity in one family

“…This observation is in line with previous findings that apathy dominates the clinical picture in patients with bvFTD caused by a GRN mutation [65, 66]. It is in contrast with bvFTD caused by C9orf72 repeat expansion, in which inappropriate behavior and agitation dominate the clinical presentation [25]. Also, the fact that four of the nine family members had PPA is highly suggestive for a GRN mutation [21].…”