A novel tau mutation, S320F, causes a tauopathy with inclusions similar to those in Pick's disease.

Mutations in the tau gene cause familial frontotemporal dementia and parkinsonism linked to chromosome 17. In this article, we describe a novel missense mutation, S320F, in the tau gene in a family with presenile dementia. To our knowledge, it is the first mutation to be described in exon 11 of tau. The proband died at age 53 years, after a disease duration of 15 years, and autopsy revealed a neuropathological picture similar to Pick's disease. Recombinant tau protein with the S320F mutation showed a greatly reduced ability to promote microtubule assembly.