Takeaway
C9orf72 expansions, age at onset (AAO) and Northern European ancestry correlates with the behavior variant of frontotemporal lobar degeneration (bvFTD), not primary progressive aphasia (PPA).
Why this matters
Frontotemporal lobar degeneration (FTLD) refers to the second most common form of young-onset dementia after Alzheimer’s Disease. The major clinical syndromes are behavior variant (bvFTD) and/or language dysfunctions, known as primary progressive aphasia (PPA).
Repeat expansions of C9orf72 have been identified in FTLD and have been reported to be associated with phenotypical and pathological heterogeneity.