SvPPA is typified by difficulties in single word comprehension and impaired word-finding, while deficits in nfvPPA language production present as effortful speech and agrammatism.11,12,13 TDP-43 causes approximately half of all sporadic bvFTD cases, and therefore one cannot identify with a high degree of certainty which patients have TDP-43-vs tau-related diseases. The gene discussed is TARDBP; the disease is behavioral variant of frontotemporal dementia.