Frontotemporal dementia and Parkinsonism linked to chromosome 17 with the N279K tau mutation.

We present a case of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) harboring the N279K mutation in the MAPT gene from the family known as pallido-ponto-nigral degeneration (PPND). This 49-year-old man was followed for 17 years. He presented at age 41 years with left leg stiffness and en-bloc turning.