PSEN1 and frontotemporal dementia: For FTD patients, five were seen in VCP, three variants each were seen in CSF1R and PSEN1, two in PRNP and SQSTM1, and one each in NOTCH3 and CHMP2B. Two DVs in PSEN1 and one each in GRN and VCP were identified in patients referred with suspected prion disease, the latter as part of a concurrent mutation with a PRNP DV.