Comparison of family histories in FTLD subtypes and related tauopathies.

Pedigrees from 269 patients with frontotemporal lobar degeneration (FTLD), including frontotemporal dementia (FTD), FTD with ALS (FTD/ALS), progressive nonfluent aphasia, semantic dementia (SD), corticobasal degeneration, and progressive supranuclear palsy were analyzed to determine the degree of heritability of these disorders. FTD/ALS was the most and SD the least heritable subtype. FTLD syndromes appear to have different etiologies and recurrence risks.