A frontotemporal dementia characterized by variable phenotypic expression typically including social, behavioral, or language deterioration, rather than memory or motor deficits and the presence of TARDBP-positive inclusions that has material basis in mutation in the GRN gene on chromosome 17q21.31. [ http://www.ncbi.nlm.nih.gov/pubmed/16983677 http://www.ncbi.nlm.nih.gov/pubmed/16862116 ]