Moreover, we included patients with genetic forms of prion disease resulting from different PRNP mutations, in particular FFI (with the D178N mutation), GSS (two with the P102L mutation, one with the P84S mutation and one with the Q212P mutation) and gCJD (11 with the E200K mutation, one with the E211Q mutation, one with the V210I mutation and three cases with 4 or 5 octarepeat region insertions). The gene discussed is PRNP; the disease is prion disease.