Familial frontotemporal dementia and parkinsonism with a novel mutation at an intron 10+11-splice site in the tau gene.

We report a case of familial frontotemporal dementia and parkinsonism characterized by early onset with mental retardation. The patient died at the age of 54; neuronal loss was severe in the frontal and temporal cortices, globus pallidus, substantia nigra, red nucleus and dentate nucleus. Anti-tau-positive fibrillary changes were observed in neurons and glia in these regions. Although the patient had 2 novel point mutations of the tau gene, P301P (CCG to CCA) and an intron 10+11-splice site (T to C), exon trapping analysis indicated that the latter was pathogenic.