The main protein has not been identified in a small subset of cases,and these are diagnosed as FTLD-U, since the inclusions are immunoreactive toantibodies against proteins from the ubiquitin-proteasome system, but not to tau,TDP-43 or FUS.5 Again, overlap withPSP, CBS and MND is seen, as FTLD-tau might underlie PSP and CBS, and inclusionswith TDP-43 and FUS can be found in MND. The gene discussed is FUS; the disease is mild neurocognitive disorder.