Progressive anarthria is usually classified as a tau pathology. We report an 87-year-old female with a family history of ALS and Parkinsonism, presenting with progressive anarthria. Molecular genetics analyses showed a heterozygous mutation S393L on exon 6 of the TARDBP gene. It has been previously reported in sporadic and familial amyotrophic lateral sclerosis. This case strengthens the hypothesis of a continuum between motor neuron disease and frontotemporal lobar degeneration among TDP-43 proteinopathies.